Bougy Fan wrote:Hi Neli I think what Paul was trying to get across was that "normal potting medium" is not what we use for growing on and DEFINITELY not in bonsai pots. The easier the water will run though the better. As a rule I use a minimum of 50% diatomite in with a good quality potting mix (one that has large pieces of bark in it) I have planted some trees in bonsai pots in a mix of just diatomite and scoria with the average diameter of the particles to be 6mm. No fines and no soil and the tree love it.
Thanks for the advise!
Why is bonsai mix, composed of large, particles used? To promote very fine hairy roots...and to prevent root rot. That is so that You utilize the space of the pot to the maximum benefit of the plant.
Do I want to develop hairy roots in the outside container? Not necessarily, since they will be chopped within the small plastic, after they thicken in order to create a nebari. All the roots that are going to grow within the inner plastic are in bonsai mix...so I hope that is where the fine roots will develop, dew to the media used.
Do I fear that root rot will happen in the outer container??? No...the soil is 100 times more drainable than the soil I use in my packets /pots...for growing pot plants. (I have a nursery) There is a layer of stones on the bottom, to prevent the holes being blocked with soil, and assist with drainage.
If you notice the growers in Asia are using ground soil to thicken the roots, after channeling them in pipes...I dont see much difference regarding the principle of the method...apart from the fact that they have much more space in the ground...If you puncture the packet some more...you can use it instead of colander, just the same way You use it with plants in the ground, for thickening the trunk. It is much cheaper...and much easier to use. The difference here in this case between the colander and my packet is that there are no holes in the middle of the packet, which I hope will promote prioritized development/thickening of the top roots, instead of all roots, since I want to thicken only the surface roots and train them..
I initially thought that he is referring to the phenomenon of too big bonsai pot filled with bonsai medium...that contains a small plant with few roots, as described by Brent from evergreen garden works:
http://www.bonsai4me.com/Basics/Basics% ... otting.htm
In this case...Part of the plant grown as bonsai is in a bonsai mix in a small packet...Then part of the plant (some roots) are grown in the outer part of the large container as a normal potted plant. This can be done in the ground also...using a punctured packet instead of colander. I shall do that with most of my hard to root reduce plants like tamarind...and some other...It is less stressful to the plant when doing root reduction, since you have the advantage of growing roots for nebari on the outside...and fine roots on which the plant can fall back when root trimmed, inside the bonsai pot /packet in this case.
Actually all my hard to transplant trees are planted in the ground with the packets...and I use the escape root which is almost the same as this...So far I had no problems...just that those packets have holes at the bottom only.Of late, for the past few month...I am making large holes at the top on most plants that are put in the ground...so I have what to compare...those without and those with holes at the top.
Well that was my logic, but I can be wrong...the results at the end will show if it works or not.