Kiyohime Japanese Maple soil

[tanlu]

Hi all,

I plan to repot a nursery stock kiyohime JM next spring into a training bonsai pot. What kind of bonsai soil (specific ingredients) should I use and how much root pruning can JM take? It has a 3" trunk and already naturally ramified branches.

Would defoliation effect the strength of the tree next spring?

T

 

[Smoke]

Yes. I would not repot and defoliate in the same year.

 

[rockm]

I don 't know if you're planning on defoliating now or next spring...

Either way, you'd be endangering the health of the tree. Defoliating now in the fall would spur a flush of new growth that would be killed off in the next few weeks. That would mean the tree had expended an enormous amount of energy for no return. It may die over the winter or next spring, as it tries to push more growth.

Next spring, if you defoliate and repot at the same time, you can severely damage, or kill the tree. A new root system (which is forming for weeks after root pruning) requires foliage to help drive regeneration.

 

[fore]

I've heard that defoliation of any kind diminishes the health of the tree overall. But i've done it myself and didn't notice any difference in health. But it was someone very experienced who told me this.

 

[rockm]

"I've heard that defoliation of any kind diminishes the health of the tree overall."

This depends on many things and is measured on kind of a sliding scale. Trident maples, for instance, can be defoliated two or three times (if they're VERY healthy and have a long growing period) a year. Japanese maples species aren't generally as vigorous. Kiyohime JM is basally dominant and weaker at the apex Defoliating the top of one of them can be tricky even in optimal growth. Defoliating the apex can kill it off...Defoliating it at the wrong time and removing its roots WILL, most likely, kill off the top...

 

[tanlu]

I didn't plan on defoliating the tree, but the most of leaves dried up and some ended up falling off, so those parts almost naturally defoliated and are now pushing out new leaves (the apex). I decided to remove the rest of the damaged leaves, which lead to an entire defoliation. I'm seeing more and more leaves every day, so I'm guessing it should be alright until next spring. I definitely don't plan on defoliating next year, but I would like to get this thing into a bonsai training pot.

What kind of soil should I use? How are their roots? Should I remove all old soil, or keep some? If so how much?

 

[fore]

"I've heard that defoliation of any kind diminishes the health of the tree overall."

This depends on many things and is measured on kind of a sliding scale. Trident maples, for instance, can be defoliated two or three times (if they're VERY healthy and have a long growing period) a year. Japanese maples species aren't generally as vigorous. Kiyohime JM is basally dominant and weaker at the apex Defoliating the top of one of them can be tricky even in optimal growth. Defoliating the apex can kill it off...Defoliating it at the wrong time and removing its roots WILL, most likely, kill off the top...

I agree rockm. You need a very healthy tree before defoliation. Interesting about Kiyohime JM, I didn't know this species. Very different from JMs.

 

[tanlu]

Here's a few photos of the tree before the leaves were damaged by the sun. I will take a few post-defoliation photos. The leaves in the apex are filling in nicely. I think it must've been quite healthy since it wasn't touched for quite some time.