Author Topic: Cork oak repot??  (Read 6634 times)


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Cork oak repot??
« on: February 04, 2013, 04:59 PM »
Should I bare root it or should I do half first? It's in nursery soil


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Re: Cork oak repot??
« Reply #1 on: February 04, 2013, 05:35 PM »
Usually with deciduous trees bare rooting is fine, but I am not sure on cork bark oak.  If you want to play it safe, bare root half of it and leave the other half for the next time you repot in a couple years. 

Someone else may have experience more specific to cork bark oak.



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Re: Cork oak repot??
« Reply #2 on: February 15, 2013, 11:31 PM »
Hey Kid,

Q. Suber is the coolest.  Dont Bareroot, dont wash, just standard bonsai potting, comb the roots, clean very well up under the crown, make upside down birdsnest and pot, no big whoop.  Get it back out in full sun, loves sun and warm.

You could wait another month...would be better

good luck


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Re: Cork oak repot??
« Reply #3 on: February 16, 2013, 06:28 PM »
I had a crop of about 20 cork oaks, and bare-rooted them all over the last 2 years.  I did lose a couple, but I was pretty aggressive in reducing the size of the rootball.

- bob

Don Dunn

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Re: Cork oak repot??
« Reply #4 on: February 27, 2013, 11:33 PM »
What type of soil is is presently potted in?


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Re: Cork oak repot??
« Reply #5 on: March 05, 2013, 04:29 AM »
Hi Kajukid, I love Quercus suber!
Need some more info on your tree: how old is it roughly? How long have you had it? Was it collected (if so how long ago?), or is it nursery stock?
A picture would be very helpful too.
But here is how I deal with them...
First up they need to be healthy and have grown well the season before.
If your repotting goal is to get rid of the soil it was collected in or nursery soil etc, repot when the buds are swelling or even just starting to push into new growth.
First up totally defoliate the tree.
Then carefully remove all of the old soil from the root ball but do NOT trim the roots at this time.
Be as careful as you can removing the old soil trying hard to damage as few roots as possible.
You can prune some branches at this stage too.
Repot into your bonsai mix (hopefully free draining, but depends on your climate and watering prefernces etc).
Cork oak love a slightly acidic soil mix and this can be achieved by adding 20% or so of kanuma (or substitute for something else if not available).
Once potted up and thoroughly watered in place your tree in a black plastic bag. This induces the tree to bud. Check the bag every couple of days and when your shoots start to grow, substitute for a clear plastic bag (drycleaning bag is ideal). Leave it in the bag until shoots extend between 5 and 10cm's in lenghth. Then poke a few small holes in the bag and over a period of two weeks increase the size and amount of the holes in the bag. Once in has adjusted to the outside climate remove the bag and slowly introduce it into morning sun and then increase to full sun etc.
Don't stress if(?) mold grows from being in the bag, it is harmless and will disperse once out of the bag.
The bag is also a good idea if you live in an area that gets snow during winter, or if your area is prone to a late flush of frost etc in early spring.
If for some reason you are not comfortable with totally defoliating your tree when repotting, just leave two leaves at the tip of every branch (to ensure sap flow) and cut them in half.
If you don't like the idea of putting them in a black plastic bag, you can skip that stage and just put them in the clear plastic bag instead.
I got these techniques of  very experienced Italian bonsai artists that deal with Quercus suber regularly and who are very familiar with this species. I trialed these methods on 6 of my subers that were collected 2 years ago and needed the old soil they were collected in removed.
All of my trees did very well and did not skip a beat! So I speak from my own personal experience.
I hope that you find this information on this species useful.
Good luck whatever you decide to do!
It would be good to learn more about your trees and your climate.
Cheers, Dario.

Leo in NE Illinois

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Re: Cork oak repot??
« Reply #6 on: March 07, 2013, 03:39 PM »
I have a couple California live oaks seedlings and Quercus suber Cork oak seedlings. I do grow in a climate too cold for too long for these oaks to survive outdoors for any length of time in winter. Therefore I winter them in a near freezing cold room, a dis-used well house that is underneath my patio, and accessed through a trap door in my basement foundation wall. Entirely below grade, hovers about 35 to 38 F even in -10 F weather. And stays below 38 F even on the days that jump into the 50's during our short 2 or 3 day February thaws. So it is a nice even temperature. But it is dark.

After a few months in dormancy I bring them into my light garden, then out in the yard after last frost.

With my climate in mind, Ted Matson recommended only working on the live oaks and Cork oak in early summer, while everything was in active growth. This is a tree where all defoliation, pruning and repotting are done on a single day, for me early June, then just let the tree grow until the following june. Of course wiring and other less disruptive tasks can be done anytime, but the pruning, repotting and defoliation should only be done while the tree is in active growth.

That was his advice, I'm in year 5 with these, and his advice has worked for me.

You are in California, so timing and perhaps the tree's tolerance of disruption may be different. Your climate is different.