Author Topic: Repotting  (Read 2261 times)


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« on: February 22, 2014, 04:14 AM »
Good Morning,

talked to my brother-in-law yesterday and we touched on repotting.

We use crushed red brick [ it's fired to a point where it does not breakdown in soil, but is still porous ] and builders gravel [ silica based ] and an organic [ home made compost ]

Looking at what we call the core [ some of the trees are from cutting or seed 33 years ago ] it was noted that the inorganic is still there, the organic seems to be constantly changing.
Constantly changing as in fresh stuff is taking the place of the older material that first decays, goes to a ball type shape and then as a powder filters out. To be replaced by more organic material.
[ checks are done for possible root thickening ]

Reading somewhere, it seems to be that compost after decaying goes to a colloidal state and rebinds as a ball before becoming so fine as be basic components and then more compost comes along and the binding part starts again or particles filter out.

We did note that if the crushed brick had fracture lines from being physically crushed, it would break a second or third time in use in the soil.

Anyhow, we do not wash the soil out, and retain a core, with a removal of about 1 to 1/2" of oild soil and these days test pie wedges to check for root thickening.

Thus far trees remain very healthy.

Note on the black pines, due to ignorance, the soils of these are now closer to the density of azalea roots in soil. Removal of old soil through wedges is a pain, and trying to get the roots to clean / raise on the surface is difficult.
Any advice ?
Thanks in advance.
Good Day

* Oh and we are able to get cuttings of J.B pines to root. What was missed is that they need to be left alone for over a year in a large container. First 2 test subjects died after transplanting.

Presently cuttings are being set in the small pockets of seed trays, so a core can be allowed to develop.
That way it is easy to life and reset in a growing on container.
This should negate the need for seed.
Any advice ?


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Re: Repotting
« Reply #1 on: March 07, 2014, 03:33 AM »
Hello Anthony,

Can you please PM me with the details on how exactly you prepared the JBP cuttings and at what time did you prepare them(ie just before the candles started moving/ after needles hardened/ after buds matured etc etc) and which part of the mother plant you used(ie hardwood shoots, fresh softwood shoots, semi-hardwood shoots). I am very interested in alternate ways to propagate JBP

ps I'm a bit confused; how often do you repot? wouldn't the fine organic matter pool up in the bottom of the pot and cause drainage problems? I guess creating a mix that would degrade(only the compost will degrade) in two years time can work for trees that needs to be repotted on a 2 year frequency. I think with black pine you will start to slow down the developement of the trees if you put them on a 2 year repotting frequency indefinitely. I've found that they are very slow for at least one growing season after repotting, and they really need their drainage to be optimal for them to truly be happy and healthy. if you can adapt your mix to stay free draining for 4 years you will have 1 year off and 3 years of consecutive developement, ive done this by changing the composted bark(or home made compost) out for non-composted bark chips. this gives me a extra few years of developement before i have to repot again. my mix for JBP atm is 25% bark chips/25% crushed brick/25% granite grit/25% expanded clay(laterite leca from spain), I stack a layer of spaghnum moss on top of the soil to preserve moisture and water them once a day from start of spring until my deciduous trees drop their leaves in autumn, then i water only once a week, and i fertilize every sunday with fish emulsion(during growing season).

Thanks in advance


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Re: Repotting
« Reply #2 on: March 08, 2014, 04:42 AM »

 nothing special is done [ see AusBonsai for the guy who did the J.B pine work ] , just clip off for training, stick the cuttings in water and later just shake off the water. Then dip into a normal rooting powder for hardwoods and put into a soil [ normal peat/perlite packaged stuff from Canada and add on some 5 mm gravel [ silica based].

Leave in a bright area, with morning sun, and keep watered. That's it. Since this is a seed tray, with soil / pine cuttings, if any cuttings die, they are pulled out and dumped. The empty space is refilled with new cuttings.

The first two cuttings were lost because the roots didn't like being interfered with, hence the shift over to seed trays. The cuttings should root bind in those small spaces and can be shifted to a larger earthenware container.

For the older trees, repotting is 3 to 5 years, for trees in small pots, repotting is yearly.

Black pine work is experimental down here, as the trees/seedlings don't quite follow what is written in the Bonsai Today books. Treating them like normal trees seems to make more sense for us.
It is still too soon to say with any confidence, just what has been adapted to and if it works constantly.
Right now, it is larger and larger earthenware pots, but not deeper than 15 cm, and colanders [ stainless steel ], no open ground growing as of yet.
However note, aims are trees at 38 cm [ weight factor and getting older, not expecting any younger hands or having to hire hands ]

The compost is consumed by tree roots, as food. An example, a test was done two months ago with a Sageretia. A soil mix closer to 2 parts inorganic to 2 parts organic [ by volume ] Visually the compost was seen on the top, when watered. Today, the top is filled with mostly inorganic, is loose, and no compost.
As stated before the compost goes to a rounded, ball-like shape seen at the time of repotting, yearly.
Fines of organic material are never seen at the base in a quantity to clog a drainage hole and with some trees, no fines are seen at all.

Also observed, trees with highly acidic qualities [ the tamarind for example ] leaves soils that are loose and falling apart, wereas
trees with an alkaline nature [ the Southern Chinese elm ] cause the soil to sheet and stick togther.
So when the respective tree types are prepared for repotting, allowed to have just moist soils, the elm always has the messy soil mix.

I am told that home is around 86 deg. F to 90 deg.F [ 30 to 33 deg.C ] by day for about half and hour, by 6.00 p.m down to low 70's [ 22 to 24 deg.C ] and by night 68 deg.F [ 20 deg.C ] humidity is around 70 % at night and as low as 55 % by day.
No rain since Christmas, and it is extremely windy.
The trees are usually placed in positions for as much sun as is possible. Water is now evening and morning.
Soon it will be twice in the morning and once in the evening, as the trees consume the compost. When the rans return May/June, the rain will not be able to affect the trees with their organic or water retentive brick mix.

Less than 15 cm per month in rain is considered to be drought conditions, but the local forests are adapted to the dryness, and soon heavy flowering will begin.
Good Day.

Yellow Poui - Tabebuia


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Re: Repotting
« Reply #3 on: March 08, 2014, 05:19 AM »
Baba A,
I also use the crushed village bricks,,,I find that the commercial ones are too hard and less water retentive. They are just like akadama.
I use mostly inorganic mix since my gardeners go in a frenzy when watering...On some trees I ahh a very little pine bark or compost.
Greetings to you and Baba K.
« Last Edit: March 08, 2014, 05:21 AM by Neli »


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Re: Repotting
« Reply #4 on: March 11, 2014, 01:28 PM »
Hello Neli,

peasant fired pottery, that is made from a stoneware type clay, will powder with time, and even return to a clay state, as the heat is not sufficient to effect a permanent change. Very poor sinter bonding.

Uncomposted material, is not used because when we did Biology for O'levels [ 5 years of study ] the idea was that the material would steal nitrogen in order to decompose. Then rapidly dump all the nitrogen back out, burning the feeder roots.
I have seen on the internet, folk try to compensate for the loss of nitrogen with heavier doses of fertiliser.

Watering in Baba K's [ Father K ? ha ha ha ha ] garden is by a plastic watering can. The exercise is excellent and water is not wasted, plus it all remains very individual.
You may not see Baba K for a while as he may get a chance to build two or three new structures.
This is something he really enjoys, mixing cement, brick laying, plastering, painting , terrazzo floors...........
Good Day