How do you Modify Al's Gritty for the HOT Desert?
In the thread in this forum on Smart Pots, I noticed that those with experience in hot areas say that these pots drain well with Al's Mix. Too well! They dry out in the heat FAST! I am in Zone 9b.
Cebury, Zone 9 states, and I quote, "I've got several Smart Pots as well as testing out a line of Fanntum Containers for my containerized fruit trees. I live in Central CA where the heat is crazy. However, only two of them have the gritty mix and I was betting I wouldn't make it through the summer in those. I suspect the gritty or 511 mix in a fabric container, in dry 100+ weather, will not work unless you are a watering maniac. I made it through last year in plastic containers with the gritty mix (added 20% more turface and reduced granite) but the hottest days did require container shading. Also the smallest containers, and one citrus tree where the roots were extensive and filled the container, required a cache pot or placing mulch around them. Those is my area scoff and say you *must* use peat or coir in every mix to survive the summer heat. Well I've certainly found that peat "bakes" (as does other media), when used in plastic containers in full sun. Just because a mix holds lots of water doesn't mean you can ignore root temps. There is not enough aeration in a heavy water-retentive soil in a plastic container for it to release the heat."
I plan to use root pruning pots for my containers because the roots don't circle, and the root mass is then much bigger causing the plants to grow faster.
Is there a way to modify the mix so that it still drains, but not so fast? I don't want the top to dry out, of course, and am going to put a piece of shade cloth over each container's top to shade the roots, and prevent evaporation, but I don't want my roots to dry out due to high heat and fast drainage, either, so any suggestions?
Will Cebury's solution of less gran-I-Grit, and 20% more Turface work?