Amadioranch

 

Posts: 27

Joined: Mon Jan 30, 2012 6:08 pm

Climate Zone: 9a

Do anyone here have any experience with leaf stripping this time of year as a way to force deciduous fruit into dormancy? Many of ours are VERY slow to drop leaves this year and I am contemplating helping them along.

Ed of Somis

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Joined: Sat Nov 27, 2010 11:46 am

Location: Ventura Co.

Climate Zone: Sunset zone 21

A...I have heard of this technique on this website and others before. I understand the principal. My guess is: it certainly would not hurt. In SoCal...the leaves begin to fall slowly because the tree is going to sleep in a warm winter climate. I suspect that the tree is in a "light sleep" already, but the leaves have not completely released. Might it be better to clip the leaf stems....rather than pull them off? I would think the leaf buds at the base of the stem should remain. Others here will chirp with much better info than mine!

DavidLJ48

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Location: San Joaquin Valley, CA

Climate Zone: Sunset Zone 14, USDA zone 9b

With a zone of 9a, I would think that some sign of dormacy is showing. This year in the US, some areas are experiences at least a 30 day retarded approach of winter. Some of my trees still have a few leaves, some had lots of leaves, just a couple two to three weeks ago. We have been mild, and cold has not really taken off the leaves, but the decrease in day light each day.

Here, on the average, get a killing frost below 32F by mid Nov, came close, but bananas made it unburned, only got down to 32.7F or so. Finally this morning, it got down to around 31-32F, there was heavy frost on things last night at midnight, at 38/39F.

This has been only the second hit close to freezing, most of the time it has been 40s to mid 60s, some times a bit lower. If your plants normally go dormant, a little more patience might be in order. I would imagine you could apply a dormant winter spray or a slightly caustic spray, and it wood take out the leaves, but have not tried them for that.

David

pitangadiego

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Location: San Diego, CA

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Leaf stripping can also be an inducement to reflush if the temps are high enough.

BayAreaTropical25

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Joined: Sun Jan 15, 2012 6:15 pm

Location: Vallejo, ca

Climate Zone: USDA zone 9b/10a Sunset 17

I leaf strip my fig tree... otherwise I'd be raking up leaves all winter long If I could leaf strip larger trees around my place I would! I'd rather do the raking all at once then over and over again through the winter months.. lol

Jacob13

 

Posts: 45

Joined: Fri Nov 26, 2010 3:24 am

Location: Southern California

Climate Zone: 10

Amadioranch,

I have had to strip leaves in the past to induce dormancy and again had to do it this year. Since our Summer was long and Winter was slow to kick in, my trees were super slow to begin dormancy. So once again I stripped leaves from my Cherry tree and 2 diufferent Plum trees. I have always had good results.

- Jacob

DavidLJ48

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Location: San Joaquin Valley, CA

Climate Zone: Sunset Zone 14, USDA zone 9b

It just hit me, reading this again, why do you rake your leaves up, don't you leave them as added mulch, or don't you have mulch on the ground, or do you compost everything first ?

David

BayAreaTropical25 wrote:I leaf strip my fig tree... otherwise I'd be raking up leaves all winter long If I could leaf strip larger trees around my place I would! I'd rather do the raking all at once then over and over again through the winter months.. lol

Ed of Somis

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Posts: 435

Joined: Sat Nov 27, 2010 11:46 am

Location: Ventura Co.

Climate Zone: Sunset zone 21

I was wondering about this whole issue of trees being stripped of leaves....and assuming that the tree is now more dormant because leaves are no longer visible on the tree. Follow me on this one....when you live in low chill areas, many deciduous trees are slow to drop leaves. Some NEVER drop all their leaves before budding out again in early Spring. However, none of my deciduous fruit trees have pushed new growth for months. Several of my apple and plum still have many leaves...so, the theory is: if I strip the remaining leaves (already pretty lifeless) that will bring on a deeper sleep to the tree??? I am just not sure those remaining lifeless/discolored leaves are catching UV"s and keeping the tree actively growing. Did any of this questioning make sense? What are YOUR ideas on this?

DavidLJ48

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Joined: Fri Nov 26, 2010 8:38 pm

Location: San Joaquin Valley, CA

Climate Zone: Sunset Zone 14, USDA zone 9b

Ed, there are many factors in a plant going decidious and even more for many to flower and produce fruit, but then I guess you are aware of that already.

I guess the thing to do is, lay out what I know reguardless if you might know it, so I am just going to let my mind free flow.

When leaves have turned to fall winter colors totally, yellow, red, orange, purple and etc, and all green is gone, the leaf is not working to provide food and energy for the plant. Though I can see that remaining leaves would indicate that the plant and roots have not gone totally dormant, some leaves would indicate some plant sap flow between the top of the plant and the roots; that the roots had not fully pulled all energy reserves back to the roots.

And have to assume you know about chill factor, which is needed to form bloom buds properly, to bloom and set fruit. Covering a wide range of plants, decideous, semi decideous and etc and evergreen, there is a wide range of chill hours needed or not needed.

I have noticed too that decideous plants, some are more triggered to drop leaves from a decrease in day light hours and some respond more to cold nights below certan temps, and they all seem to be a mix of the two, dependent on the plants native condtions. I have seen a time or two, here in the Central Valley, that stone fruits never fully dropped leaves until mid winter, the winter being so mild, waiting for mid winter and colder temps. Then have spring temps and more daily sun hours kick in a month or less later in mid to late January. Just luckily we got enough chill hours below 45F to fix the bloom buds.

I know that Axel has done some studies and observations on planting plants needing more chill, in the more shaded areas of his property. I have noticed in my yard, that the more shaded areas, stay colder longer, where there is no direct sun. I have wondered if spraying ones trees with something white or reflective, would have a similar affect on a tree. Less direct sun on the bark, should prevent the wood from warming up and giving it the wrong signal to stay active; allowing the wood to stay colder. I guess leaf stripping might help this along, to get the spray coverage you need. There are things I would think, you could spray on the tree to help, to get a good cover of the limbs, but spraying the reflective ???, might drop the rest of the leaves too, But if using flat white paint, may not want all of that on leaves, on the ground eat year. I know that there are commercial sprays to drop leaves.

The coating would help those who have earlier spring bloom/fruit killing freezes. I know that commerical tree growers in marginal areas, paint tree trunks and some even the lower limbs, to help slow/stop early spring growth, before the area really warms up, to delay bloom, when it would be safer.

thinking more off the wall, and if your tree was not too large, what about throwing a reflective plastic thermo like blanket over the tree and if need be, stick a small frig or ac unit under it on your colder nights for more chill, so energy usage would less. I guess this idea is not green or ecological freindly, but when brain storming, just go with the flow and evauate things later. I wonder how long it would take for dry ice to totally evaporate if you covered a tree and put a small chunk inside. I guess maybe also too expensive of a idea.

David

Ed of Somis wrote:I was wondering about this whole issue of trees being stripped of leaves....and assuming that the tree is now more dormant because leaves are no longer visible on the tree. Follow me on this one....when you live in low chill areas, many deciduous trees are slow to drop leaves. Some NEVER drop all their leaves before budding out again in early Spring. However, none of my deciduous fruit trees have pushed new growth for months. Several of my apple and plum still have many leaves...so, the theory is: if I strip the remaining leaves (already pretty lifeless) that will bring on a deeper sleep to the tree??? I am just not sure those remaining lifeless/discolored leaves are catching UV"s and keeping the tree actively growing. Did any of this questioning make sense? What are YOUR ideas on this?

Ed of Somis

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Posts: 435

Joined: Sat Nov 27, 2010 11:46 am

Location: Ventura Co.

Climate Zone: Sunset zone 21

D...a very thoughtful and thorough response from you. You have covered a lot of ground....and made some great points! I remember a few years ago while considering the whole east coast-leaf colors tour...I was suprised to learn that the primary trigger for these trees to shed/sleep was diminishing daylight hours. Certainly, when you are talking about next year's fruit....chill hours are critical on deciduous fruit-bearers. I actually remember reading another's post... telling about how he stacked ice cubes around the base of his tree in winter. I am thinking most of us fruit growers are a bit nuts, anyway.