DavidRoussel schreef : Dus een Akadam/Bims 50/50 zou best goed zijn of eerder bims 60%?
Per Walter pall:"Substrates: Good substrate material must: be of equal particle size, have the ability to absorb water and release it back, have no fine particle organic material, must not decompose easily, be as lightweight as possible when dry, preferably inexpensive and should have an aesthetically pleasing appearance. This would then be: lava, pumice, baked loam, Turface, zeolite, Chabasai (a type of zeolite), coconut pieces, bark pieces, Styrofoam pieces (no joke) and a few more which you can find yourself if you have understood the principles. Please note: Some of these materials may not be available in your area.
Normal akadama is questionable as a good substrate as it inevitably decomposes, especially when exposed to winter frost. It can become deadly loam in the pot, choking the flow of water and air into the soil. This is especially true for trees which are only rarely repotted, like collected conifers and old bonsai in general.
Substrates which are not useful: soil, compost, stones, sand etc. Trees grow in sand and flower soil, of course, but it is not an optimal growing medium for health in bonsai culture.
All substrates can be mixed according to your liking and it makes almost no difference. They can also be recycled and used again, but make certain to sift and clean any recycled materials as needed.
There is no such thing as an 'ideal bonsai substrate'. There are in fact thousands of ideal substrates. I believe that IT DOES NOT MATTER WHAT YOU USE AND IN WHAT MIXTURE as long as it is a modern substrate.
Since there is no soil in modern substrates there is very little alive in them. They dry out easily and one must water several times a day when it is hot, especially if you have used pure inorganics. Therefore I add rough peat in addition to the previously mentioned substrates. This is the kind of peat that is harvested in bogs and comes in its natural coarse form. Make certain not to use fine particle peat/sphagnum moss, even if the package says “dust free” as the particles will be too small. If you cannot find the correct type of peat, use small bark bits without dust particles, or cut coconut fibers. These organic components should comprise 15-20 % of the overall volume, a bit less with conifers, olives and such, and a bit more with small trees and azaleas."
