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Gardens of Resilience

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Good afternoon and welcome to Smithsonian  Gardens Let's Talk Gardens, a weekly webinar  

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series that we hope to give you information to  turn your brown thumb green. As always we have  

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a terrific program for you today but before  I introduce our speaker I like to give you  

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a few housekeeping tips. Please we're not going  to raise our hands or answer raised hands today  

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in the presentation but please put your  questions in the chat box after the presentation  

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we will be calling upon those questions and I'll  be giving them to our presenter so that he can  

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answer them to his full ability also for optimal  conditions make sure that all your other browser  

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windows are closed and just have this one open  so you'll have the best viewing conditions the  

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best video connection possible and if you are  in the D.C. area please come down and visit us  

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our gardens are open they're gorgeous and the fall  colors are really starting to shine. So we invite  

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you to come down and visit no time tickets nothing  to get in your way just come on down and share  

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the beauty with us. We'd love to see you in our  gardens. So for today's presentation very timely  

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in the mid-Atlantic area we just looked at the  weather and it's going to be colder much colder  

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this weekend so you need to start thinking about  bringing in your tropicals if you haven't already  

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and today's presenter Matt Fleming is our tropical  specialist at the greenhouse in Suitland. So Matt,  

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how are you? Great thanks for having me and  everyone for joining the talk today. Well terrific  

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we're going to find out a little bit about our  audience to help you out during your presentation  

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because you and I were talking and we're trying  to find out what plants I should bring in, what  

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plants you're going to bring in, so I was going  to go ahead and share a poll with our audience  

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and find out first what do you consider  tropical what zone do you live in  

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here in the mid-Atlantic area or a strong zone  seven maybe even sometimes going into a zone eight  

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and then we wanna know what you're bringing  in. So I just placed it up on the screen  

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if you would please go ahead and vote we'd really  enjoy hearing from you and to see where you're  

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from and then what you're going to be bringing  in that will help out Matt because he has to  

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think about bringing advising people the staff  downtown to bring all their containers in as  

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well as dig some of their favorite tropicals that  they overwinter then in the greenhouse. Oh Matt,  

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do you see this it looks like most of our visitors  are from Zone seven so they're that's great the  

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middle Atlantic area so you'll know all about  that composition yeah and mostly containers so far  

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but they do have a mix of tropicals that they  are bringing in so that's pretty cool. We have  

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I'm gonna leave this up just for a couple  more seconds but then I'll share it with  

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our audience so that they can see what's out there  we do have some people in zone 9 and zone 10 so  

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there are some warmer areas that work with so they  might be able to leave everything outside. Let's  

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find out with their information so I'm going to  end the poll and share the results with our public  

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and say 68 is from zone 7 and 81 are  looking to bring their containers  

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in that have tropicals inside them so. I am going  to disappear and leave it up to you please tell  

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us more about yourself and your experience and  jump right into today's program. Thank you Matt.  

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All right, well thank you Cindy and thanks  for everyone for joining us today. I hope that  

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you get something out of it and if we do have  any technical difficulties bear with us but  

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knock on wood hopefully we should all be well.

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So we are going to talk about bringing in your  tropical plants basically it is going to be  

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overwintering and in the simplest form  overwintering is the art of not killing things.  

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Over the winter and that's basically my job  so a couple things about me I have worked at  

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Smithsonian Gardens for almost 11 years now 10 of  those which have been in the tropical department.  

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so I've learned a lot made some mistakes and hope  to share some of those things with you all today.

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I hate to weed! It is part of life if you work  with plants it's just something I don't like to do  

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overall I'm not that good at pronouncing  genus and species names so be mindful of  

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that when you're talking with friends  and everyone that we all make mistakes.  

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Yes I have certainly killed plants before a lot  of plants and even this awesome one pictured here.  

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Luckily it was not too far gone where I was  able to take a couple cuttings and we have  

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two pieces that are now probably four years  old that are I don't know, every bit of a a  

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foot a foot and a half tall. So while the mother  has since gone we have her baby still alive.

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So I'm assuming most of you  over winter tropical plants  

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popular choices include hibiscus various tropical  vines Pacifloras, mandevillas some succulents  

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brugnansia, bananas are another popular  one then you have your bulbs, tubers,  

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rhizomes, your cannas your cold acacia, dahlias  things like that palm trees majesty palms eurekas  

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and then also herbs and vegetables as  well like rosemary or even pepper plants.

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So the first thing we got to do is we got to  decide what to keep and I don't really like to  

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think of it as what are we keeping but more why  are we keeping it. One of the things to consider  

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is maybe it has sentimental value to you. It was  your mom's, your grandmother's something like that  

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and it has a special place in your heart. So  you know no matter the circumstances that's  

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getting saved. My wife and I gave out african  violets as wedding gifts for our wedding and  

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I'm obviously not getting rid of that  because I want to stay married and  

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just you know if it's important to you and you  want to keep it go ahead. It also could be a  

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rare species or cultivar it may have taken you  a long time to acquire and if you were to get  

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rid of it over the winter then it's possible  that you wouldn't be able to find it again.  

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Just remember cultivars come and go can be both  a good thing and a bad thing. It's good because  

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certainly new and improved things can come out  lots of new things to try. It's bad in the sense  

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that maybe you had a hibiscus that you just  loved and you know it finally, finally came by  

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the wayside after a long time you went to go buy  another one and it's not being offered anymore so  

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something to think about. Finally maybe it's a  large specimen that is going to be hard to replace  

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maybe you have a you know 30 or 40 year old  jade plant that you know you're not just gonna  

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be able to find another one  at a local garden center so  

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don't want to throw that away . Two pictures  I have on here the left one is just a  

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picture of kind of how I try to utilize all  the space that we have in the greenhouse. We  

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have a couple big philodendrons so I stack them  up on pallets and then we put the ferns underneath  

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because they don't mind the shade but with the  philodendrons raised it just allows us to have  

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a little more space on the right is probably a  20 foot tall triangle palm brings us back to you  

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know a large specimen we're not just going to  go to Home Depot and get another one of those  

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come spring. So that's obviously something  that we're going to keep from year to year  

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so seriously though go crazy what what do you  have to lose it. It is a tropical and if it's  

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going to die you know or you're going to throw  it away why not give it a try you can do things  

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like whack the root ball back you can chop the  top back. You know do whatever you can to make  

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it work for you and your situation. Plants  want to do two things, live and reproduce.  

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They're certainly gonna help you win but it's also  okay if you lose as well and the last thing to to  

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kind of remember is it doesn't have to look that  pretty over the winter and if a friend comes over  

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and you're really worried about it hide it for a  couple days it will be as awesome as you remember  

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it come May and that's all that matters as long  as it's alive over the winter that's our goal

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Of course there's going to be a lot of  limiting factors on what you can and can't keep  

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one of the main probably the most important  thing is space. Do you have a greenhouse  

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in your backyard sure then you know  fill it up and keep whatever you can.  

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Maybe you have a two-bedroom apartment where  your couch takes up half of your living room then  

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you're not going to be able to keep as much and  you have to take that into consideration time.  

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Your time to do you work 10 hours a day and you  know gardening or construction and you just want  

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to go home and relax. Maybe you're retired and  you have all day to you know take care of things.  

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Another thing to think about is how long are you  willing to spend watering and performing other  

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chores as needed every week and the the plant  needs, is it a high or low maintenance plant.

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is it something that you're gonna  have to cut back a vigorous vine  

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or is it just a succulent that is gonna be  slow growing and not gonna need much attention  

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obviously the big thing is how much water is  it gonna need is something you have to water  

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every day maybe it's gonna go dormant  and you don't have to worry about it  

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and then finally cost and the cost is going  to be if you want to replace it come spring  

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maybe it's a large specimen  like we kind of spoke about and  

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if you were to try to find one it  would be an arm and a leg to replace

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So what do we do before they come in? Scouting  one of the most important things that you can do  

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you should obviously be doing that anyway pests  a lot of different ways you can take care of,  

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things you can simply squash them like if  they're aphids or mealybug things. Like that  

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you can cut off part of the plant that's infected  or you could spray it with a simple soap and oil  

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too if you have a little bit of a  higher population to knock it back.  

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Just remember though a small outbreak  outside is gonna equal craziness inside,  

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where outside you have birds other insects kind  of helping you, inside you're not gonna have  

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any of those friends so populations are going to  going to go much higher and much quicker as well  

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if it does have a disease nine times out of  ten. In my opinion you should just trash it  

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don't put it in the compost pile though because  what you don't want to do is have it over winter  

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then come spring you're spreading out your  compost and you're giving everyone a little  

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phytophthora a little, little pythium for you.  Whatever the case so just trash it diseases  

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they're just not worth the risk and the hassle  risk as in spreading to other plants that you  

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may have hassle as in they are not the easiest  to get under control. A lot of times you have to  

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spray you know two three times in back to back as  well as clean up any of the affected leaves so if  

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it has a disease and it's not you know something  that you can't live without just get rid of it  

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fertilizer. Basically we just want to make sure  that we have enough so our plants aren't starving  

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we don't want them to be pushing growth but you  also do want to start with a healthy plant for  

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the long winter ahead. One thing you can do  is to move plants to a semi-shady location  

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just to get a start on acclimating them to the  lower light levels that they are going to be  

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getting all winter long indoors so make  life easier on yourself you know if you can  

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cut back any vines or wood a's that do respond  well to pruning which is honestly most of them  

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it'll save space and water needs at least for  a little while and anything that can go dormant  

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let it go dormant the ones that most of us know  you have your cannas your caladiums colicacias,  

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other tubes and bulbs and tubers some that  you may or may not know bananas, plumerias  

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and pepper plants. So the picture here is just  of Acalypha that we have the one on the right is  

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how it was sent back to me the one on the left  is cut it back and I did the right one as well  

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after taking this picture. This is actually  a picture I took literally like last week.  

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One of the gardens sent back a bunch of their  hibiscus and the left picture is how I received it  

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root's all a mess you know the top kind of grown  out. So what I did is I cut back probably 10 to 12  

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inches all around the plant and didn't do too  much to the roots because it had a a decent  

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root system on it and potted it up and that's  what it's going to look like over the winter.

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So let's talk a little bit about dormancy. You  know there's a lot of people from different areas  

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on here from the pole. It does seem that most  of you are kind of in that zone seven area so  

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it's going to be very both  plant and location specific  

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but you know here are some  generalities to factor and kind of  

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think on. You should probably stop fertilizing  about four weeks before the first frost and  

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whatever you plan on bringing that plant in you  again you don't want to be feeding the heck out of  

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them so they're growing like crazy once you bring  them obviously you want in bring it in at the  

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appropriate time cold sensitivity for the plant we  have some plants that you know can stay out till  

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Thanksgiving. We have other plants that it gets  below 50-55 degrees and it's going to show you  

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that it's mad and it will have some cold  damage so all going to depend on the plant.

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Is it going to go completely dormant is it a  bulb a rhizome something similar or is it more  

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as i just like to say you know is it going to  chill and relax over the winter like a lantana  

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or plumeria things like that. The key really is to  keep the plants in a cool dark place. When I say  

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cool about 50 degrees give or take a basement,  garage, crawl space things like that often work  

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well . Some things do need to be watered from  time to time where others need no water at all.  

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So we're going to talk about  a couple specific things,  

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a couple specific plants and anything special that  may pertain to them. You'll notice some things are  

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kind of repetitive but we'll just talk about those  quickly. So your cannas caladiums your dahlias  

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things that have a rhizome or a tuber . They're  going to go into basically what i call full  

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dormancy. So what you should do with those in  most cases you want to let a light frost hit them  

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then dig them up set them somewhere to dry out for  a few days preferably somewhere with a little bit  

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of shade. But you do want good air movement around  them cut back the foliage to just a couple inches  

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then brush as much of the soil off as possible  you can store them in dry peat moss sawdust  

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wrap them in newspaper and store them in  a cool dark place. You're going to hear me  

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say cool dark place a lot with dormant  plants because that that is important,.  

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Remember though it certainly is a good  idea to check on them occasionally  

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specifically check on any of any of them or  rotting you want to remove them the saying  

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that one bad apple can spoil the whole bunch is so  true with bulbs and tubers and things like that.  

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So when you check them you just want to  give them a squeeze and if there's any  

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any soft spots or anything like that  most likely you just want to toss it  

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and depending on your  situation you can pot them up.

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And start bringing them out of dormancy about four  to six weeks before the last frost in the spring  

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to get a jump start on larger plants

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So plumeria and brogmansia i consider  them kind of more semi-dormant  

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you can cut them back especially the brogmansia  they respond so well to a hard pruning plumeria  

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do as well but you're gonna have about four  or five shoots from any pruning that you have  

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so you may want to go in and then thin  those out when they start to break bud  

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again. Keep it in the cold dark place they both  will likely lose their leaves and watering wise  

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again it's going to depend on how hard you cut it  back how big of a pot things like that but about  

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two to four weeks depending on your situation. One  nice thing about plumeria they have a real fleshy  

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thick stem and you can you can squeeze them and  if they start to feel mushy you want to water them  

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we want a nice hard turgid stem. Bananas are  very popular one so if they're in the ground  

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you want to dig them up cut back  the top to a more manageable size  

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clean off some soil around the roots ideally  you want to probably store it sideways  

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in a basement crawl space something similar

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you can keep it in a pot as well cut it back store  it in a cold dark place again. Probably water it  

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about once a month or so the soil doesn't pull  too far forward away from the edge of the pot.  

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I have had some times cut it back to like a foot  let's say in the top few inches because there's  

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so much water in the banana it starts to rot  the growing point so just be careful of that.  

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It's another reason why it's important to keep it  in a cool dark place but just something i had have  

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noticed and ran into time and time again if it  does happen a lot of times if you just cut right  

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below the rotted part it will flush  it will flush new growth and be fine.

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Peppers lantana and some similar plants like that  again they're gonna kind of go semi-dormant if it  

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was in the ground dig it up throw it in a pot  cut it back. They all respond great to pruning  

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keep it in a cool dark place they'll likely  lose their leaves again water every two to four  

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weeks depending on your situation you don't  want the soil to completely dry out though.

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Herbs such as rosemary and oregano things like  that if it was in the ground they get up and repot  

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obviously they respond well  to being cut back because  

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well we cut them when we use them when we're  cooking and you can enjoy herbs over the  

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winter . There are some things like rosemary for  example that can't be overwintered in the ground  

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so in cooler locations it will need  to be brought inside and that too can  

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kind of be kept semi-dormant over the  winter like a lantana or a pepper plant

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things that don't go dormant  but you just want to keep

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maybe it's palms, hibiscus, vines things like  that if it was in the ground dig it up and repot  

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move it to a semi shady location again to  get acclimated to the lower light levels  

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a week or two is fine you  don't need to go too crazy.  

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I'm big on whacking things back I've mentioned  it a couple times both the shoots and the roots  

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as needed and again it's going to come down to  your situation and what your needs are and your  

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space and things like that. So if you have a  plant that is going crazy maybe it's a vine  

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just whack it back again. It its getting  too big for you or you can simply start over  

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collect seeds and replant. A lot of the  vines come up very easily from seed and  

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they tend to grow fast take cuttings and start  fresh before you take cuttings and get rid of  

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something you might want to see how how well the  cuttings take before getting rid of something.  

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If you take a dozen cuttings and none of them  take and you already threw away the the plant  

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you're certainly not gonna be too happy so maybe  keep it for a year and make sure the cuttings take  

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if you take a dozen and ten stick then next year  you could probably be safe and throwing it away  

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a lot of plants can be divided sins of area things  like that easy way to save on space give some to  

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your friends neighbors things like that just  to note to remember some plants do need time  

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to heel over so they don't rot before repotting  sands of area especially you want to heel over.

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So what to do with them over the winter obviously  you want to water at proper times. Each plant is  

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going to be different both or plants that are  the same but maybe are in different containers  

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are going to have different water needs scout  and manage any pest, disease issues, to feed or  

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not to feed them. In most cases i lean towards no  fertilizer over the winter if you see an obvious  

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issue you can certainly address it but you just  don't want them pushing growth in inside it's  

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going to be weak leggy and just not not something  you want to try to push. Rotate your plants. We  

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don't want any leaning tower of hibiscus. I would  say you know get on a good habit of rotating them  

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once a week and finally we want to water it the  proper times. Oh wait we already talked about  

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that didn't we? Yes we did because that's probably  the most important thing that you can do over the  

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winter is is watering at the proper time you don't  want to underwater you don't want to over water.

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So spring is coming. Wwhat you can do is start  bringing plants in pots that were dormantthat  

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maybe aren't getting planted directly in your  garden out of dormancy? Just remember that less  

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water is better rot is going to be your biggest  enemy for the first month or more things that like  

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you cut back maybe or that respond well to a good  cut back cut them back again. Hibiscus bromancia  

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things like that winter growth is often very  weak and leggy. So if you were to put it outside  

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get a decent windstorm a lot of those branches  are gonna snap on you so give them a good pruning  

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timings is going to be very dependent on your  needs and the growth of the plant as well.  

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Once outside and acclimated  you can start to feed but  

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don't go too crazy in the beginning you have all  season you don't want to burn any of the new roots  

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so we'll talk briefly about timing take this with  a grain of salt this is basically for me in the  

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D.C., Maryland, Virginia area in the greenhouse  for gardens that need to be perfect come  

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may so usually i'll stop feeding in November i  may feed once a month from November , December,  

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January and then when the days start to get a  little bit longer I'll go to every other week in  

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February at about a half of half the normal rate  and for us we don't keep any bulbs or tubers in  

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like a box or bag or something like that. What  we do is we pot them up now basically water  

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them once then we won't water them again  until basically the last week of February  

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and I'll go through and soak everything really  heavily and then i won't do anything again for  

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two weeks and then i will water them again and if  the soil has really started pulling away from the  

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outside of the pot. I'll kind of go through and  rough up all the edges so the water isn't just  

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running right off before i water them again that  second time and then i won't water them again  

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until the plant tells me it's time and what i mean  by that is after that second watering you know a  

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week two weeks maybe more. Hopefully, there the  bulbs are going to start waking up the caladiums  

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are going to start pushing growth we have a lot  of amorporphous phallus things like that and  

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if you keep watering them they're just going to  rot. And even if you do see them pushing growth,  

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dig to the side a little bit and check because  you know an inch under the top dry level of soil  

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it could be wet and those bulbs and tubers  obviously had little to no roots all winter.  

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So over watering is your biggest enemy at that  point. Just a couple things that i cut back  

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we cut back a ton of stuff but these are just  some examples i pulled at different times  

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hibiscus i cut back in mid February.  They seem to be a little bit slower  

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especially after a hard pruning it  takes them a while to break again.  

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We have a lot of cane begonias. I'll cut  them back to just a couple nodes in mid-March  

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shrimp plants in early April the acalypha  hat i showed a picture of a lot earlier  

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cut them back in mid April and acclimation is  all going to be temperature implant dependent and  

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it can vary from from year to year but i would say  you know mid April is when i try to start bringing  

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things outside and getting immaculate acclimated.  This is just a picture of euphorbia continifolia.  

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The picture on the left was taken right before the  one on the right basically i cut it back really  

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hard and it will it'll flush growth again and  then start to look great come the warmer weather.

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These are two different species of Tibouchina. The  one on the left we kind of made into a standard  

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the one on the right is just a bush form again all  that winter growth is going to be weak and leggy  

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so you want to get that out of there a great time  to put plants outside depending on the weather  

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is right after a hard pruning they won't need  to acclimate to full sun so that picture of the  

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euphorbia. It's a little bit more cold  hardy so basically as soon as i cut it back  

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i'll throw it right outside in full sun so the  new leaves can be acclimated as they come out  

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just saves on on time and in effort of moving  them around and finding shade for them.

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So acclimating your plants when they do go  back outside this is something we're all  

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guilty of I've done it many a times sunburn can  certainly be the biggest issue cold obviously  

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one thing not to forget is wind you know it  may be let's say 48 degrees but if you got 10  

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-12 mile an hour winds all day constant it's going  to be a lot colder to those plants especially any  

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new and tender growth it they'll be a lot  more susceptible to cold and or wind damage  

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certainly don't want to set them right outside in  full sun after they've been indoors all all winter  

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if you can put them somewhere where  they're going to get a little bit of shade  

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if you can't bring them out for a few hours at  a time every day slowly working up to all day.  

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It's better to start maybe late morning as opposed  to you know two or three o'clock in the afternoon  

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when the the sun is at its you know strongest  and if you don't have any place to put them under  

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shade or anything like that you can certainly  bring them out in any overcast or rainy days

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Lastly just to kind of finish up on a few points  most of us here are probably all plant dorks  

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and we hate to trash a perfectly good plant  but there are times when we just don't have any  

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other choices again cutting seed those are good  alternatives and you're gonna kill some things  

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from time to time and that's all right that that's  part of being a gardener and honestly if you're  

33:46

not killing anything are you really trying it's  part of just that you know the business and or the  

33:56

the passion that we have try new things if  you kill something it gives you more space  

34:01

to try something else. Just remember new doesn't  always mean better. Just you know as an example it  

34:09

seems while it's not a tropical it seems that  there are you know 50 new echinacea cultivars  

34:16

that come out every year and just because  it's new doesn't always mean it's better  

34:22

push the limits of your zone if it you know if you  don't have room for it and it dies again so what's  

34:29

the harm. Not in all winters are created equal and  what i mean by that is i think it was maybe two or  

34:37

three years ago we had a a really cold cold winter  and then i believe last winter it was very mild  

34:49

and we had a lot of things in some of the gardens  downtown not even die back that normally do die  

34:54

back so you know if if you keep something out it's  possible that it may live for a couple years then  

35:01

we have a really cold winter and it may die but  at least you got to enjoy it while you could.  

35:07

One last thing remember if you're keeping  anything dormant or semi-dormant the  

35:14

the key really is to keep plants in the dark  and keep them chilly it just kind of helps

35:24

them stay dormant and not want to  push growth. So that is all I have.  

35:31

I did want to say thank you to everyone that  joined us today and Cindy for putting this on.  

35:38

I hope everyone has enjoyed all the talks  and especially this one so thank you  

35:45

thank you matt if you'd stop sharing your screen  they can see your face a little bit better and we  

35:50

haven't we're we are having a little bit of sound  problems with your microphone so just stay close  

35:56

to the mic and just make sure that your mic is  actually on your shirt on here. So just make sure  

36:03

it's unencumbered and that will help out but you  are not done because there are a lot of questions  

36:08

that people want to know about so i want everybody  to know that we may not get a chance to ask your  

36:13

specific question but Matt will do his best to  answer the questions afterwards and we'll post  

36:18

them up on our website but most importantly for  specific questions about pests that you may have  

36:26

i would look at your extension agents or extension  office handouts or on their website because your  

36:36

past have different stages like scale you can't  take care of unless it's in a specific stage  

36:43

and some of the other things so look  to see inform yourself first. But  

36:47

the one thing that people really want to know what  is the right watering routine. How do you tell  

36:54

if the if you need to keep it watered or not as  in dormant plants or just watering it over the  

37:01

winter in general? I think just watering in the  winter over general but also hit upon the dormant  

37:07

plants so that that is probably one of the most  asked questions i get is when do i water or how  

37:16

how often should i water and it's probably  also one of the hardest questions to answer  

37:22

let's say that you have a 20 foot tall palm tree  in a 12 inch pot probably not realistic but it's  

37:32

going to be all roots and you probably couldn't  give that thing enough water whereas if you had a  

37:39

newly sprouted seedling where it barely has even  true leaves and its cotyledons and you put it in  

37:46

a four foot pot you're probably not going to  have to water again before it's done before  

37:51

it dies. So the biggest thing about watering is  get to know your plants and what i mean by that  

37:58

is as you kind of check on them every day you'll  start to get a good understanding of how fast  

38:05

they do dry out and the the two things that i do  besides taking into consideration what plant it is  

38:14

is it a succulent is it something that grows in  you know sandy soils or it needs a lot of water  

38:22

is you know your finger stick your finger  in in the soil the top couple inches are dry  

38:29

most likely needs water you can also lift  lift them up if they're not too too heavy  

38:36

dry soil weighs a lot less  than than heavy wet soil. So  

38:41

those are two things but also use your eyes  if the soil you know looks dry to you and is  

38:47

pulling away it's definitely time to water  but again a lot of times the top layer of  

38:53

soil inch or so can can be dry but beneath it  can be wet so i know that wasn't a specific  

39:01

answer but it just varies too much depending on  the plant and the container size that it's in  

39:08

you know especially with bringing tropicals in if  you whack it back cut the roots back a little bit  

39:16

it's not going to need a lot of water for you  know maybe a month maybe more and if it's wilted  

39:24

it may not need water it just may be  that the plant is you know suffering  

39:28

right now from getting mutilated by cutting back  everything so again don't just water based on  

39:36

its it's wilting it may not be that that the  soil is dry it just can't take up enough water  

39:43

because again you cut back a lot of its roots so  you gave a really perfect example of what you do  

39:51

at the greenhouse because i want everybody to  understand we have the gardens downtown in D.C.  

39:55

around all the different museums and then we have  the greenhouse which is the support center for  

40:00

all those plants the greenhouse grows most of the  annuals that you see down in the gardens downtown  

40:06

and the greenhouse also supports all the tropical  plants over the winter so you can imagine how many  

40:11

plants matt has to water over the winter and  getting ready so lifting up the pot is a really  

40:18

good suggest because you can't stick your finger  in each one of them so lifting up a pot as you  

40:23

go down is is really a helpful hint and one that i  think more people should take advantage of and i'm  

40:29

sure that's what you do with the greenhouse in all  your support of the tropical plants from downtown  

40:34

yeah and you know Cindy brought up a good point we  have three greenhouses chopped full there are some  

40:40

things so yes we have three greenhouses chuck  full of plants there are things that i water  

40:44

every single day we have some tree ferns that  once they dry out they're gonna show you their  

40:51

mat so i water them every day 365. There are  some things that get watered maybe once a week  

40:57

then we have other things that the dormant or  semi-dormant plants that may not get watered  

41:01

for months and it it all depends and the more  you grow and become familiar with your plants  

41:08

you're going to know you know their needs  as well now one group of plants you didn't  

41:14

talk about overwintering or citrus plants so i'm  wondering if you have any special tips for citrus  

41:21

i know i have a lemon tree that you guys grew  from seed for one of our programs garbage gardens  

41:28

and and it's now a big lemon tree so what do  i need to do specifically for that so we have  

41:36

a couple citrus that we overwinter we  don't have the lemon anymore just because  

41:43

for display purposes anytime a lemon would would  fruit it would somehow magically get stolen  

41:51

and lemons don't look that great without  fruit so we ended up getting rid of it but  

41:59

citrus aren't much different than anything  else you can certainly cut it back as always  

42:05

but you know biggest thing would just be to  water it at the right time it's it's it's not  

42:11

gonna do a whole lot it's obviously a pretty  tropical plant so over the winter the day days  

42:17

are shorter it's going to be cooler. Basically  you just want to keep it alive over the winter  

42:23

kind of like i was saying it may not look  that great give it as much light as you can  

42:28

the more light the better but nothing too  special. I would say to be honest with you  

42:34

i think the only special thing that i do  for citrus but this could be for any plant  

42:39

is when you bring it in you might not you might  have treated it for pests whatever so you don't  

42:44

have a large problem but all of a sudden  you have an explosion again say in February  

42:49

and that's usually because that buildup has been  occurring all along and you don't notice it too  

42:54

you have a big amount so for most of my plants  i'll put them in my shower maybe once a month or  

43:00

so and individually so i can really pay attention  to them i do i do this it's it's a a loving  

43:07

situation for them and i give them a shower so i  hose off all those mealy bugs i hose off all the  

43:14

flies all the white flies whatever is the  problem and you're right it doesn't look perfect  

43:19

but it gives them an opportunity to not have this  outburst all the time so you do it because you can  

43:25

overhead water really easily in the greenhouse i  can't do that in my living room so that's a hint  

43:30

i've picked up through the years is give them  a shower play some opera they might appreciate  

43:35

all the attention to go along with it so and  somebody else how do i keep the ants out of my  

43:42

home when i bring in my pot so i know what i  do what do you do so that's a good question.  

43:49

Unfortunately ants are not the only thing  that i deal with we get mice sometimes in  

43:55

the drainage holes and they'll make a nest and  like that first couple times that are all water  

44:02

you'll see mice just run it everywhere and  it's it's gonna depend on your situation  

44:09

if it's a small plant ideally if it was in a pot  you i'd take it out and check the roots and before  

44:17

i brought it in because if you bring them in it's  gonna be a lot harder to to get rid of so but  

44:23

there's a lot of products dusts and drenches that  one or two applications can take care of it but

44:33

i would say the biggest thing would be to check  them before you bring them in i agree because i  

44:36

don't get ants i get pill bugs which really  entertains my cats but it's not great for  

44:43

rats oh and somebody said thank  you for warning them about mice  

44:46

that's true mice do come in sometimes  so hate the greenhouse if you  

44:52

that's how if you have a greenhouse and i'm sure  most of us are lusting after the greenhouses if  

44:59

you saw the wonderful greenhouses that  matt works in you would be lusting too  

45:03

but do you have to keep those greenhouses heated  in the winter time to keep the tropicals alive

45:11

again it's going to depend on what what  you're keeping if if all you're doing  

45:17

is just trying to kind of keep things alive  over the winter and you're not worried about  

45:22

how they look again you can force a lot of things  into dormancy that you wouldn't think of like  

45:29

you know plumeria obviously doesn't go dormant  in Hawaii but here we force it into dormancy by  

45:35

cutting back on watering it drops all its leaves  it helps me space wise and as well pest wise  

45:43

so you can kind of force things into dormancy  keeping it a lot cooler but if you have you know  

45:51

palm trees and and things like that that you know  a lot of palms are a lot more cold sensitive than  

45:57

than you may realize so it's going to depend on  what you want to keep and the temperature more  

46:04

at night is going to be the most important factor  so it it's again it's hard to answer without it's  

46:11

going to be dependent on what you what you want  to keep yeah and what zone you're in right yeah  

46:16

and i think just the main thing is don't let it  freeze so don't actually don't let it get below  

46:21

about 45 degrees so that that's an important thing  because if they're dormant 45 degrees is still the  

46:27

temperature that you want to get the lowest at  and of course if it's it's alive it'd be much  

46:33

warmer so that's a good tip why here's some banana  questions why do you store the bananas sideways

46:44

I don't know why it's done i guess to me it's just  to help it for me it just helps them think that  

46:52

it's kind of dormant time that you know  they're cold they're in a a cool location  

46:58

i'm not going to lie i don't know why i've just  always been told that so you were told to do it so  

47:05

that's what you do actually i don't i do a lot of  mine and and the reason that i turn mine sideways  

47:10

is to remember not to water them and also  to it keeps the roots a lot drier and  

47:16

if something's in the greenhouse and somebody sees  it laying lengthwise they don't want to water it  

47:23

so that's i think that's the most important thing  so just remember to keep things that are dormant  

47:28

not watered as well as you would if you try to  keep them alive so the other thing that they  

47:34

had a question about and this is something i've  learned as an outdoor gardener because i'm more  

47:39

of an outdoor horticulturist than a tropical  but i have learned that the the question was  

47:46

how do they overwinter some of their tropicals  outside and this is a real key thing is because  

47:56

for our temperatures in zone seven a lot of  plants would survive outdoors if you have them  

48:03

planted so that they drain really well and they  don't get too wet in the wintertime so for your  

48:10

bananas somebody's putting mulch bags over top of  them that's fine do you find the same thing that  

48:16

if it if it stays dryer it seems to live longer in  the garden yeah so that's a that's a good question  

48:25

in in in bananas and there's a lot of things  cannas things like that you can do it with  

48:31

wet feet is probably one of the biggest things  for any any plant that you're trying to you know  

48:37

that's marginally hardy as it is you don't want  to keep it wet because then it's not going to have  

48:44

a strong root system so but yeah  there are certainly things you can do  

48:49

dig them up put them against the wall of your  house to kind of radiate heat put leaves mulch  

48:56

over them different things like that but said it  a lot it just depends on where you live the zone  

49:06

the plant things like that but as a generality  certainly the wet the wet feet is a good  

49:14

is a good tip it really is it really  does make a difference so if you have  

49:18

something that's marginally hardy putting  it in well-drained soil that maybe you've

49:25

added some grit or some heavy sand not not the  fine sand but the multiple multi-particle size  

49:34

sand that seems to help quite a bit and again  to keep it dryer by maybe putting a little  

49:40

cover on top of it to be able to keep it a little  bit drier sure so yeah people go to great lengths  

49:47

yeah i mean i've seen people put chicken wire  around even like some japanese maples that are a  

49:52

little bit more cold and just fill it with leaves  over the winter just to give it a couple degrees  

49:57

so you know certainly get creative and  do whatever you can to keep your babies  

50:03

yeah the strangest thing i've ever seen but it  worked was to wrap cactuses outside or some of  

50:11

the succulents outside wrap them in plastic and  put Christmas lights inside of it because for  

50:16

the heat from the old-fashioned Christmas lights  not the leads they don't do the same thing but  

50:20

the old-fashioned Christmas lights will give it  enough heat to keep it alive and somebody just  

50:24

asked that what is the best way to overwinter  cactus on a covered porch so those of you that  

50:31

have visited Smithsonian Gardens if you see a  gentleman around the hopped garden Michael is  

50:37

notorious for doing the the Christmas light trick  there are a couple agave and other things that  

50:48

again they're kind of marginally hardy and he's  been known to come in on a Saturday afternoon he  

50:54

puts plastic around it and he'll put the Christmas  lights underneath it just to give it you know if  

50:59

it's supposed to be in the teens or something like  that he'll do that trick and and it does help it a  

51:06

lot of times it's a couple degrees can make a big  difference so yeah again do do whatever you can to  

51:14

to make it work and so the person that asked  about the cactus is i would say try one outside  

51:20

on your porch not all of them and see what it  does because it just depends on how low your  

51:26

temperatures get and how how protected your  porch is this is another good one what's the  

51:32

best type of pot to use to overwinter your plants  if you're trying to keep them alive not dormant  

51:40

i mean the only thing so there's a couple ways you  can look at it if it was in the ground just throw  

51:46

it in a cheap nursery pot that you know you you  would get an azalea in at a garden center if if  

51:55

it was in a you know a nice fancy terracotta  or glazed pot as long as it has drainage holes  

52:03

in it you're going to be fine the biggest  thing is just make sure it has drainage holes  

52:09

and a good well-drained mix to be honest with  you there's there's not much difference between  

52:16

containers in all reality just find one  that fits the size of your plant and it is  

52:21

appropriate for you know you don't want it too  big or too small so i think that's the best key  

52:28

fit the size not necessarily the material but the  size to your plant i always find that i over water  

52:34

so for me terra cotta is best because it dries  out a little bit quicker many of us underwater  

52:39

so maybe plastic would work better for you i like  you have a fancy container i'm gonna call it that  

52:46

doesn't have drainage holes in it you could keep  it in a nursery pot and then just slip it in and  

52:53

out too. So there's the thought because you don't  want to bring in anything without drainage holes  

52:58

over the winter or you're going to have wet feet  and problems yeah because somebody said how do  

53:03

you lift your heavy plants to put them in the  shower so that's what i do i keep them in the ugly  

53:08

nursery pots and then slip them into the fancy  pots inside so it's not quite as heavy i know  

53:14

i'm gonna have to stop doing this eventually but  maybe i'll build a shower on the deck i don't know  

53:18

maybe that'll come out or shower like at the  beach outdoor shower exactly yeah everything is  

53:25

on the deck that's what i do a lot of my things go  out on my deck this is a good tip though because  

53:30

we're both from zone 7 and zone 8. So Bob wrote  to us that there are those of us who are in the  

53:36

arid or semi-arid areas too dry for many plants  with sustained freezing temps can also be deadly  

53:42

for plants that can otherwise be overwintered  outdoors and that is very true in fact i found  

53:48

that there are people in Massachusetts that  can keep things alive in the winter because  

53:53

they have a deep layer of snow where we don't so  our temperatures fluctuate too much. Sometimes  

54:06

have to be a detective when you're trying to  overwinter your plants yeah now the women there  

54:12

was a couple other one i really wanted to ask you  about there's a good one that someone wrote about  

54:19

for those of you that that may not have a basement  to store your bulbs and tubers and rhizomes in  

54:27

it's going to depend on what you what you have and  what you don't have but a garage is certainly an  

54:35

option if you don't have a garage simply a closet  in maybe a cooler area of the house and trying to  

54:44

think of of other things but we have because it's  not super cool or dark doesn't mean you can't  

54:53

overwinter but you just have to watch them a  little bit more especially the rotting and yeah go  

55:02

for it again if it's not going to make it either  way try a couple different spots in your house  

55:06

and see what works out the best and see you know  see what works right we have a volunteer that has  

55:13

a guest room that she keeps the temperature very  low in so that's where all the plants go over the  

55:19

wintertime so i always thought that was a great  tip too if you have an extra room that nobody  

55:23

sleeps in all the time keep the temperature down  low it keeps the guess away too so that's good too  

55:30

well right now maybe that's not a problem so  another one was if you have something outside  

55:37

that's getting ready to flower and you've waited  all year and now it's going to freeze what do you  

55:41

do do you leave it in the ground and take  the chance or do you put it up right now  

55:49

again i've said it a lot but it's gonna depend on  on you really if you can dig it up bring it inside  

55:58

maybe just put it in the garage overnight and you  know a little space heater whatever the case or  

56:04

or you know just leave it out there and fingers  crossed but trust me i know how how hard it is  

56:12

when when a cold snap comes because everyone's  sending things back back to us and but it  

56:20

it's hard to give you a good answer but if you  can bring it in that that's probably the safest  

56:26

but it's gonna depend on what you can and can't do  so how big it is things like that so do you have  

56:33

a resource and education resource that would list  a tropical plant with the temperature that it can  

56:40

withstand have you ever seen something like that  there's a lot of good places i would trust more  

56:46

the .edu's and Missouri Botanic Garden is  a great that's probably one of the best  

56:55

resources if i just had to pick a random one  is Missouri Botanic Garden they have a great  

57:03

listing of all their plants that they have  in their gardens and it will say minimum  

57:06

temperatures and things like and things like that  so that that's probably one of the better ones  

57:11

yeah excellent that's also where you can  find out zones or you can go to the USDA  

57:16

plant map with the zones on it if you're going  to determine the difference between San Jose,  

57:22

San Francisco and Ottawa, Canada to be able  to see what your zone is what you're doing so  

57:29

another thing is this is this is a different one  i never thought about this i know we do it in our  

57:35

coolers at the greenhouse Smithsonian Gardens does  if you have something like a colocasia or a dahlia  

57:42

that you don't have a basement to keep  cooler would you put it in a refrigerator  

57:47

over the winter. i would make sure i knew what  the temperature of that refrigerator was i would  

57:58

assume it's probably 35 to 40. i'm just guessing  i i truly don't know the actual temperature of  

58:05

most refrigerators but i've said it once i'll say  it a hundred times it's gonna depend on the plant  

58:14

know what you have and what what its heartiness  is down to i think that the easiest thing is  

58:22

just just put it in the closet  over the refrigerator to be honest  

58:27

i think it will be fine okay so you have how  many plants are you looking forward to receiving  

58:34

in the next month that are going to be brought  back to the greenhouse so people understand  

58:41

what numbers you're working with sure so yeah a  quick synopsis of what happens basically about  

58:52

now depending on temperature and things like that  everything that was on display around the museums  

58:57

and our various gardens will either get dug up if  it was planted in the ground or if it was kept in  

59:03

a decorative pot it'll be shipped back in the  pot and my job is to either repot it or keep it  

59:11

alive all winter then come spring make sure it's  perfect and send it back down again but it it's a  

59:22

a task to get some of these you know we have  a gardenia that was pretty much a wide load  

59:28

hazard that i cut back to like twigs this winter  and it really it really is a team effort bringing  

59:36

things to and from the facility here in suitland  which is about i don't know probably less than  

59:42

10 miles from the mall bringing them back and  forth but um this year due to Covid a lot of  

59:49

our items didn't get put on display unfortunately  but in some years you get a early early cold night  

59:57

and it's like a mad dash we're making trips  back and forth sending as much stuff as we  

60:02

can you know i literally just shove it in  the greenhouse as long as the door can close  

60:08

that's a win so but it's it's it's a challenge  bringing things back and forth so i wanted to  

60:18

give you all hope when the next couple weeks when  you're thinking about bringing in your tropicals  

60:24

at least you don't have to do the numbers  that matt does so i have confidence in you  

60:29

bring in the ones that you love like matt says  don't worry about the ones that you don't love  

60:34

because next year is always a new year and you can  buy more tropicals and put them in your garden so  

60:40

i want to thank everyone for joining us today.  Thank you Matt for being such a great presenter  

60:47

you're starting to sound like a  lawyer at the end well it all depends  

60:52

hopefully the sound wasn't too bad so no but  thank you and we'll see you again next week.  

60:57

Next week we get to have our arborist join us  and he's going to talk about pruning which is a  

61:04

a very timely subject to talk about because people  are thinking about what are they going to do over  

61:09

the winter to re-enhance their shrubs and trees  so thank you for all see you next week. Thank you.

 

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