Do tropicals have or need a dormancy period? Follow up: can one keep a tropical in an unheated greenhouse as temperatures fall below 50deg. F?
I bring my tropicals indoors when it consistently gets below 45°. Think of where they typically grow. Mine are still putting out new growth. I’ll probably do a light fertilization soon.
Most tropicals are genetically programmed to grow year-round. There are a few - not sure how many - which are drought-deciduous; I would presume they need an annual dormancy corresponding to the dry season in their native range. You would have to investigate the species’ requirements.
I’m not sure tropicals will necessarily suffer if kept between freezing and 50 F for a short while, but that is speculation.
Definitely bring tour tropicals inside if the temp gets below 40°F. The cold will cause the water in the tree to crystallize and cause the cells to rupture, it also denatures the chlorophyll. The end results are the leaves blacken and fall off, the branches that freeze will start to die back. They shrivel and dry up, same with the roots. They will do quite well outside in temps > 40°F and will continue to grow. However, many true tropical species simply don’t have the adaptations to survive intact while in a ceramic vessel outside when the temps are below that.
Thanks to the both of you. Pretty much confirmed what I thought. I have bougainvillea which do OK in the winter unless there’s a hard frost or freeze. But I don’t trust my ficus outdoors in temperatures less than 50°… Thought maybe they’d get some kind of protection if placed inside somewhere but, thinking about it, I guess that doesn’t make a lot of sense. Cold is cold. Even if protected from the wind. You’re consensus regarding dormancy satisfies my question in that regard. I guess then it’s OK to fertilize and grow them year round? but in that case how does one know when to repot, root prune, defoliate or prune if it’s always growing (like the one I have)?
Great questions. I fertilize my tropicals with am organic 1-1-1 liquid fertilizer during the winter when it is brought indoors. I do this weekly, I water every 48 hours. If it’s a warmer day and I’m at home I’ll take it outdoors for the day. If the tree is outdoors I water it daily. The liquid fertilizer cuts down on the fungus nats. I find repotting depends on the age of the tree, size of tree and container, type of substrate used. I try to leave the tree in the container as long as possible, which for my tropicals is about 2-3 years for a young tree and about 3-4 for and older tree on average. I know its time to repot when I notice that the water sits on the surface before it begins to flow through the container. I feel tropicals can be repotted almost any time of year, winter included because they should be protected.
I don’t usually defoliated my tropicals, unless I’m looking to reduce leaf size all at once or I can’t clearly see the structure. I can tell you the longer you leave them in the container the smaller the leaves become because of the constriction of the root mass. So basically I don’t defoliate often. I will cut large leaves in half, but it really doesn’t need to be done very often once the tree is being refined.
As far as pruning goes, I let branches run until I get the thickness I want. Then I cut back to lateral branches, or leaves of desired orientation. I let those grow until I get the length of thickness I want, they cut back again. When you cut back the growth the dormant buds are stimulated and begin to form and elongate. This process in and of itself creates your ramification that reduces the size of the leaves, combined with constriction of roots in container.
Essentially, don’t worry about the size of the leaves during your development or growing of the structure. Just get the size and shape you want. Then grow your primary branches, if you already have them then start building your secondary and tertiary branches.
The foliage will get small quickly from there. The largest leaves are usually at the ends of the growing branch tips. When you prune, they are removed.
A few things about defoliation, I would do it in the early summer when the tree will be vigorously growing. I would perform it only if your tree is super healthy and vigorous and has been well fertilized for several months prior. Removing the all the foliage severely weakens the tree, it can take 2-6 (on average 4) weeks to flush out new leaves before it grows actively again. That’s a lot of lost time! Do this too many times or perform on a already weakened tree and you might lose branches, the whole plant, or stress the plant to the point where it takes it a really long time to recover. More lost time…
My tropicals don’t go to exhibits, so I don’t defoliate them as a means to reduce leaf size. I really only defoliate them when re-working structure to better visualize what I’m doing. I do think that partial outer canopy defoliation would be a preferable to a full removal.
liviing in austin TX we only freeze 2-3 times a year but get down to high 30’s regularly. just as easily it can be 60-70 the next day. i have a mini green house and put them in if it gets below 40. haven’t had issues in 2 years with my tropicals. i have bougainvilleas, barbados cherries, dwarf pomegranates. they all grow in winter.
A green house would be another great option to shelter tropical and subtropical species. I would also consider the use of a poly-tunnel.
Nicholas and Nathan; thank you. Really appreciate your response. Both Informative and useful. Very much appreciated.
@ndavila80 what fertilizer do you use? I’ve been using diluted Morbloom which is 0-10-10.
Currently using Dr Earth 1-1-1 with 11%Seaweed/Kelp extract weekly. I’ve used in past with good results Alaska 5-1-1 fish fertilizer, True Earth 111, Fox Farms liquid fertilizer, and a 3 part grow/bloom/micro, and Neptune’s Harvest.
Sorry for the necro post; when do ppl usually work their tropicals? I have one that was repotted in the spring and has recovered nicely. I need to do a decent styling/pruning on it. It’s currently indoors. Do I do the operation in the spring or in the summer after it has put on new foliage or can it be done now?
They generally like to be repotted in the summer, when it’s very warm. Depending on how you’re overwintering it, it might be ok to do it earlier, but better to wait until summer.
It’d be a styling/pruning, but I suspected that it would be better to do it once the heat came. I’m just being impatient. Thanks!
I have done a fair bit of pruning/styling in the winter, particular if they seem to be growing decently. Seems to work out for the tree and is particularly good for the grower. I agree that warmer/hotter weather is better for repotting - I like highs of >80F, >27C.
I do some styling and pruning in the winter with no problem, as long as it’s not really drastic. Save the heavy duty work for summer. Go ahead with light to moderate work if it’s growing well for you. Good luck!