Best time/frequency to defoliate a privet?

[Rustinj74]

I'm new to bonsai and figured I'd learn by starting with a pretty hardy species. I dug up a privet in February and it's already looking nice (pictures soon). I'm curious about what time of year to defoliate and how often. So far, I've just been pinching and wiring. Im not sure if it's climate dependent, but I live in Alabama and I don't believe they ever drop their leaves here. Any tips would be greatly appreciated!

 

[JudyB]

Hi Rustin, welcome.
Can I ask why you are defoliating? I only ask because the purpose of defoliation for the most part, is either to get smaller leaves (for bonsai that have reached a finished or nearly so state) or to have a second flush of leaves for better fall coloration. Since privet mostly gets the same color no matter what, you may not need or want to defoliate, unless you have a "finished" tree.
Even in Alabama, once the leaves have served their purpose, and get old enough, it will shed the old and put on new leaves. You may not notice it so much, as it may happen a few at a time, but it'll do it on it's own. When you defoliate trees, it slows down the growing process, so with your fairly newly collected tree, you may not want this. Looking forward to photos!

 

[PaulH]

I've got several privets and have defoliated them as much as three times a year and they just keep going strong.

Judy, there's a third reason to defoliate. With privets each defoliation gives you a new burst of buds and the tree ramifies that much more quickly.

Paul

 

[JudyB]

Thanks Paul, I was unsure about that, which is why I said "for the most part".
I haven't had very much experience with privet... I have a small one, perhaps I should give that a shot!

 

[Rustinj74]

Thank you both for the input! Judy, it is the ramification I'm after, but I was unaware of the other effects. These things grow so fast, they're already shaping up nicely. However, the rapid growth also makes it hard to keep up with just pinching alone, so many of the branches are long with only a lot of ramification on the end. I'm hoping the defoliation will encourage more bud development to fill in some of these gaps.

Paul, does the time of year matter, or just the time in between each defoliation?

regards,
Justin

 

[PaulH]

I don't know about your local climate but here in Northern California I start defoliating in late May and this year I did it again at the end of June.

 

[JudyB]

You should post us a picture, so we can see it! And if you can please update your profile with where you live so people can give you advice based on climate.
cheers!

 

[Smoke]

Most people think defoliating increases ramification.

It does not. It only induces a second flush of buds at the junction of where the buds were before you stripped the leaves off.

To increase ramification, the tree needs constant pruning. This is not stressful to the tree and induces emergency auxins which promote lateral budding which increases ramification.

Do as pictured below every week all spring and summer and you can triple volumne in one season.

Continue defoliation and sooner or later the tree wil respond by not budding at all. Defoliation would only be done for a late summer exhibit such as the one just finished at REBS in August when someone would want fresh green leaves, otherwise defoliation adds no significance to the branchwork in a tree.

 

[Smoke]

Another myth about defoliation is leaf size. Defoliation does not decrease leaf size. Ramification decreases leaf size. Leaf size is dictated by the trees need for photosynthesis. Sycamore trees have large leaves because they are compound and not very well distributed in the canopy. A foot long branch may only have four leaves on it so they have to be big. An elm tree has fairly naturally small leaves because a foot long branch may have a hundred leaves. The two branches may produce the same amount of sugar but one does it with four leaves while the other does it with a hundred leaves.

Increase the amount of twigs with leaves and the leaves will reduce on their own. No magic here, just natures way.

here is a small shohin size maple with leaves the size of my pinky nail. No defoliation on this tree.

here is a leader on a maple that is about twelve feet tall with leaves as much as four inches apart. Growing strong and increasing girth in the trunk but doing it with leaves ten times larger than its small cousin.

I can make the leaves on this tree as small as my pinky nail in two years with just diligent pruning

 

[Adair M]

Al, I'm not sure I entirely agree...

Well, I will say that your technique works for you and your maples.

I have a zelkova that I defoliated this year, and it produced new twigs where the old leaves were. I'd say on 75% of the old leaves, I now have a twig. So, if I had a branch with 4 leaves, after defoilating, I now have 3 or 4 twigs with leaves. That's an increase in ramification!

By all means, do what works for you.

Cheers!

 

[Smoke]

Al, I'm not sure I entirely agree...

Well, I will say that your technique works for you and your maples.

I have a zelkova that I defoliated this year, and it produced new twigs where the old leaves were. I'd say on 75% of the old leaves, I now have a twig. So, if I had a branch with 4 leaves, after defoilating, I now have 3 or 4 twigs with leaves. That's an increase in ramification!


By all means, do what works for you.

Cheers!

Think about what you just said and get back to me. Think about your process.......really think.

 

[Adair M]

Ok, Al, I'll think outloud... (Hopefully, I'm really missing something insightful!)

I had a zelkova twig, about 4 inches long, that had maybe 6 leaves on it. I shortened it to 4 leaves. (I did this all over the tree.) Then, I took every leaf off. I used sissors to cut them off. Now, I had a bare tree. In about a week, new buds swelled and popped. Now, every branch had 3 or 4 new twigs going where before I had a leaf. Each one of those new twigs, I have pinched back to 4 leaves.

I now have at least 3 times as many twigs as before and 4 times as many leaves. The tree is the same height as before I started. The new leaves are generally smaller than the original leaves. Just 4 times as many.

Tell me, have I missed something? If, truely, there is a better way, I'd be all for it. I'm doing a broom style zelkova, by the way. (Not that it should make any difference.)

Adair

 

[Smoke]

I have two trees here. One is an elm, not unlike zelcova and another trident.

I am not going to do anything to either of them.

I have defoliated the trident so you can see the structure. This is not due to defoliation this is due to directional pruning, clip and grow. The only way a trident should be devolped. It is not pruned since you said that only defoliation is necessary to ramify this tree.

The elm and the trident are about the same size, both being just shy of 6 inches tall with a 3/4 trunk.

You tell me what to do to the elm and we will do it. We can watch the development over the next few months. I have plenty of time as second spring will be here next week. Then I am good untill early November.

Both the elms and the tridents are workshop material I am growing for the shohin convention in 2014. I have 8 of each like this. All broom/spreading-oak style.

Those are the leaves defoliated off the trident.

 

[Smoke]

Ok, Al, I'll think outloud... (Hopefully, I'm really missing something insightful!)

I had a zelkova twig, about 4 inches long, that had maybe 6 leaves on it. I shortened it to 4 leaves. (I did this all over the tree.) Then, I took every leaf off. I used sissors to cut them off. Now, I had a bare tree. In about a week, new buds swelled and popped. Now, every branch had 3 or 4 new twigs going where before I had a leaf. Each one of those new twigs, I have pinched back to 4 leaves.

I now have at least 3 times as many twigs as before and 4 times as many leaves. The tree is the same height as before I started. The new leaves are generally smaller than the original leaves. Just 4 times as many.

Tell me, have I missed something? If, truely, there is a better way, I'd be all for it. I'm doing a broom style zelkova, by the way. (Not that it should make any difference.)

Adair

I don't think you missed a thing except the pruning part

 

[Adair M]

Al, as you know, chinese elms and Zelkova are similiar, yet different. The CE have much shorter internodes, and naturally smaller leaves than Zelkova.

But, what I would do, based upon my prior post would be to shorten the whips back to the canopy profile, maybe one or two internode lengths back into the canopy. Then defoliate all the leaves, cutting the leaves off with sharp sissors right at the stem.

While it's defoliated, I'd remove any interior crossing branches. For brooms, I like the branches to be reaching up like a Y. It appears there are some branches coming off the trunk at too much of a horizonal angle. With all the folliage, I can't say for certain what needs to be done. Remove them? Wire them? Bunch them up with raffia or haystring over the winter? Sorry, I can't tell what to do about that from the photo. Is there a bit of reverse taper there where the branch on the right is? Also, it appears that there is no taper above where the first branches start. Again, maybe there is, I can't properly tell from the photo.

Now, I will have to say, I'm not a shohin kind of guy! I've seen your work, and it's excellent. So, I'm not trying to say "I'm right, you're wrong", I'm here to learn new tricks, and share those that have worked for me.

But, as I said, if I'm blind please enlighten me!

Thanks,

Adair

Edit: I think our posts crossed!

 

[tmmason10]

I'd love to see these progress Al.

 

[jkd2572]

Yes thanks al. Proof is in the puddin.

 

[Smoke]

Most people think defoliating increases ramification.

It does not. It only induces a second flush of buds at the junction of where the buds were before you stripped the leaves off.

To increase ramification, the tree needs constant pruning. This is not stressful to the tree and induces emergency auxins which promote lateral budding which increases ramification.

Do as pictured below every week all spring and summer and you can triple volumne in one season.

Continue defoliation and sooner or later the tree wil respond by not budding at all. Defoliation would only be done for a late summer exhibit such as the one just finished at REBS in August when someone would want fresh green leaves, otherwise defoliation adds no significance to the branchwork in a tree.

Al, I'm not sure I entirely agree...

Well, I will say that your technique works for you and your maples.

I have a zelkova that I defoliated this year, and it produced new twigs where the old leaves were. I'd say on 75% of the old leaves, I now have a twig. So, if I had a branch with 4 leaves, after defoilating, I now have 3 or 4 twigs with leaves. That's an increase in ramification!

By all means, do what works for you.

Cheers!

Here are the two quotes. Mine is post 8 yours is post 10. Can you tell me what is missing in post 10 that would have caused me to continue on this thread with pictures of trees. One thing that would have made your post make sense?

If this thread had stopped at post ten, if I had not come back to challange this line of wisdom no one here would have known that before defoliation you cut back to 4 leaves. You could cut back to four leaves on any diciduous tree and increase ramification without defoliating. You will not increase ramification significantly by defoliating only and not cutting back. Cutting back is the key, defoliation has nothing to do with it.

 

[Rustinj74]

Thank you for the great detailed descriptions and discussion! I've updated my profile (zone 8a, Birmingham, AL). Based on my limited experience, when I prune these back, it induces two new buds at the tip and forms a new "Y"- shaped structure, but no bud induction below the terminus. Al, from what I gather from your posts, the only way to develop the gaps would be to prune it back to the gap and rebuild the ramifications from scratch? I had hoped to induce more lateral buds by defoliating. I have 3 or 4 of these things, some without much potential, so perhaps I'll experiment on one I don't care about and document the changes. I've been putting in long hrs at work this week, so I'll upload some photos this weekend.

On a side note, I see how this species is so invasive--I took a couple of 1" thick X 6" long "sticks" I was going to toss over the fence and decided to jam them straight into the ground (literally, just a section of my yard) to see what would happen. They are now small bushes, after only 6 months!!!

Thanks again for the insight!

Justin

 

[PaulH]

Cutting back is the key, defoliation has nothing to do with it.

You are correct, of course. Cutting back the meristem is always part of my defoliation process and what initiate the bud pop. But defoliation does seem to stimulate the tree into a false spring accelerating the bud growth. I agree that too much defoliation will weaken and even kill a tree. It should be used with caution.

That said, there is one more situation where I defoliate. Defoliation seems, in my experience, to help certain broadleaf trees to survive collection and transplanting. Live oaks in particular survive collection at a much higher percentage if they are defoliated. Also maples, liquidambars, and others can be repotted in the summer if they are defoliated when they would not otherwise survive the experience.