Defoliation for dormancy?

[JudyB]

I have now read in a couple of places that there is merit to defoliating tropicals for dormancy. I'm not sure I understand the concept or the timing for this. Can someone please explain this technique, and when during the winter it is most useful? I have an olive, a Brazilian raintree, and an oak that are inside during the winter. I wouldn't really think about defoliating the olive, as it's better to do all work on that tree when it's growing strongly in the summer. The raintree continues to grow all winter, so I don't know if that would be useful for it. But my suber oak, might benefit from such a thing...

 

[jk_lewis]

I'm far from a tropical expert, but I can imagine no biological reason for doing this and if those trees were mine would NOT do it. The trees will be unhappy inside, anyway and you will simply be stressing them.

Why is the oak indoors?

 

[october]

Since tropicals are generally inside for the winter. Pests infestations can get pretty bad. When this happens, defoliating the tree and spraying pesticide can be a very thorough in eliminating pests. However, I am not sure about timing etc.

Personally, if not for the reason I mentioned. Like jkl said, there seems to be no reason behind it.

Rob

 

[JudyB]

The oak is a suber, and likely will not survive in my cold greenhouse. I've heard many different opinions on this, some say it can withstand cold temps, most say a few days below 40 and it will die. I've also been told that as its a Mediterranean tree, that dormancy isn't required, much like my Eu olive. I have a good indoor setup for these trees, and have kept them happy and insect free for many years. The oak is new this year, so we will see. The rain tree gives me almost as much growth in the winter as in summer. Right now the olive is still putting on about an inch a week, inside!
There was a post on the thread about winter silhouette that defoliating is helpful to the tree, but not for insect issues.

 

[Redwood Ryan]

I don't defoliate my trops very often, as it causes a lot of stress to them. Occasionally I will, but not to let them go into dormancy, which I'm not sure defoliation would really help with that...

 

[edprocoat]

I once defoliated 3 of my Ficus because of scale infestation that I just could not get ahead of. As tropical have no dormant time, usually growing year around, the trees just put out new growth.

ed

 

[bonsaibp]

I think keeping the oak indoors is a mistake it'll do fine in the greenhouse especially if you use heating pads as you've mentioned before. In any case I certainly would not defoliate it either way but especially not if it's going indoors. I don't believe that it'll do as well as the olive indoors and it's going to get stressed. Defoliating would just really stress it. I suggest the greenhouse. I have friend in the central CA gold country foothills who keep their out all year, sometimes it even snows, I believe Brents are probably keep outside as well and he gets pretty cold( for me) in the winter. Jsut my 2cents worth.

 

[tmmason10]

I've read of people defoliating their ficus before bringing the inside for the winter. But his is just because ficus will sometimes drop their leaves in order to adjust to a new level of light, and defoliating speeds up this process. I'm not sure why defoliating woud cause your tropicals to go dormant or why this would be beneficial.

 

[Poink88]

I prune my tropical trees before bringing them inside just because I need them smaller to fit the indoor (garage) space. During this indoor winter growing, most of them get pruned twice (so as not to block each other). Not the best but works for me.

I do not defoliate any of my trees...though it could be close to that when I do hard pruning.

 

[GO-OK]

I defoliate mine twice per year. Once when I bring them in for winter before they go under the 1000w metal halide light....and again before they go out for the summer. This does not stress them at all, it is beneficial in that ramification improves and the leaves are acclimated to their new conditions.

Not sure about the oak, but seems suspect to bring it indoors.

 

[Neli]

Judy
there are two different things here.
One is the procedure you mentioned, and Unless you have a good reason to do it, there is no real need for defoliation.
The secont thing I meantioned is:
In tropical climate deciduous trees that need winter resting period which is hard to provide in warm climate never drop their leaf in winter, and in general decline if not provided with cold resting period.
In Asia, in countries with warm climate, they have been experimenting with defoliating this kind of trees, in winter, to help with dormancy, and they have managed to make them survive for a long time now using this procedure. Without it they dont survive.

 

[Anthony]

Neli,

if you need cold in the Tropics [ lowest temperature - 55 deg.C [ 13 deg.C ] no chance of frost ] chuckle - get a refrigerator or build a cold room.

The cork oak must have some dormancy or it will slowly die. [ been there, done that.]
Good Day
Anthony

 

[Neli]

Yes Anthony. Not all trees will be helped by the defoliation process, but for some it helps.
I plan to go the fridge way too for some trees, though I dont like the idea and some people told me it did not work for them. I might give some of my rest needing trees to friends in SA, and play around with few in a deep freezer and see how it goes, for experiments sake.

 

[robbase99]

Cork Oak

Hi Judy,

I bought a cork oak from Brent at Evergreen last year. I purchased it by mistake as I misunderstood its hardiness. However, last winter it stayed outside in my climate (zone 6) except for the coldest times of the winter when it was in my unheated garage without lights. I did bubble wrap the pot and mulch the surface well. It did fine with this treatment. I plan to try the same this year. Good luck with yours.

Rob

 

[GrimLore]

My Wifes tropicals are several types of Ficus and they defoliate when we bring them inside. Some have already started new budding and they will defoliate again in Spring when we put them back out. They have been doing it on their own for many years now.

Grimmy

 

[jk_lewis]

This does not stress them at all,

Now THAT is patently untrue. Removing the leaves from ANY tree at any time is stressful. (Even deciduous trees are "stressed" when they drop their leaves voluntarily for the winter!)

Your trees may survive fall/winter defoliation, but it is 100% unnatural for tropicals to be defoliated at any time, and doing it when things start to get cold is doubly so. I routinely defoliate my willow leaf figs in the summer months (sometimes twice) to encourage ramification, but they are growing strongly then. As far north as you are, Judy, they have been undergoing a certain amount of stress already as the nights cooled.

If, after you bring them in, they lose their leaves or some of their leaves, they do that because of stress. NO point adding to it.

 

[JudyB]

rethinking inside

I'm starting to rethink yet again... What I don't understand is that if this is a true mediterranean tree, they don't get dormancy there. Is that not correct? So why would it need it?
But I suppose with the heat mats, I may be ok. I'll just keep it in the warmest spot I have...

 

[Poink88]

I'm starting to rethink yet again... What I don't understand is that if this is a true mediterranean tree, they don't get dormancy there. Is that not correct? So why would it need it?
But I suppose with the heat mats, I may be ok. I'll just keep it in the warmest spot I have...

Exactly our point. It doesn't. I agree with jkl.

Edit: Just to clarify, my response is for tropical trees...NOT Mediterranean trees.

 

[Anthony]

Anyone thought of asking Alexandra [ My nellie ] she lives in Athens, Greece.
Good Day.
Anthony

 

[Dav4]

I don't have much to add to the discussion other then to mention that dormancy is induced primarily by shortening days and not cooler temps....cold temps maintain dormancy. I would think trees from milder temperate climates still experience a dormancy. but a shorter one. Do they need it??? I don't know.....