The mix you describe is very free draining and probably not very suitable for deciduous and other thirsty species unless you can be there whenever the trees need watering. It would be suitable for pines. To amend it for deciduous trees you might consider adding some finer material like fine akadama, clay or peat or finer composted pine bark or coir. Later, when the trees are in need of finer ramification, this (and the particle size), becomes more important. You have not mentioned the particle sizes you intend to use. You may also find that unless you keep on top of your feeding program your trees may suffer from certain nutrient deficiencies. A Lack of iron is usually the first to show up, but copper, manganese and sulphur as well as others are possible. Zeolite has a good Cation Exchange Capacity so it's unlikely you will have deficiencies in ammonium, magnesium, potassium and calcium. I would recommend using a slow release type of fertilizer (nutricote, osmocote, organic cakes) with this kind of mix, supplemented with liquid feeding if necessary. As shibui mentioned, unless you understand the properties of what you have, you may be better off using a general potting mix which conforms with the Australian Standard (guaranteed correct nutrients, ph, CEC, Buffer Capacity etc) particularly for things like elms and maples, and sifting out the fines if there are too many and simply adding some sand/gravel to adjust the drainage properties if necessary. It is most likely you will have better results with this.Keels wrote:
was looking for serious answers.
I hope that was serious enough for you..
much much too straight & not enough taper?"
thanks treeman. Appreciate the response. I'm attempting to expand my understanding of what makes a good soil mix for trees i have. Ill post tomorrow photos of the soil sizes and what else ive put into the mix.
