I live in semi-arid northern Utah 6b/7a and have an area of the yard that provides a microclimate with decent wind protection and 9 or more hours of sun exposure, where I would like to plant a couple of persimmon trees.
I actually planted one very small one there last year, and it leafed out and seemed to start some growth, but by summer it dropped its leaves and died (fails the green test), despite a 50% shade canopy. I suspect the soil might have been too wet.
I decided to take advantage of our crazy warm non-winter February weather and excavate the area in preparation for backfilling with better soil. Currently, ground consists of: an inch or two of bark mulch, followed by 12-18” of rich garden soil (a mix of compost and sandy loam which stays quite wet), followed by a 6-10” compacted layer of coarse granite sand and baseball/softball-sized river rock (had to use a pick), followed by a 6-8” layer of coarse granite sand and a bit of clay, followed by 24+ inches of less-coarse sand (not as fine as playground sand). I sent a sample taken from a mix of the top 24” for analysis, and it came back as “normal” sandy loam @7.7ph, except being high in phosphorus.
I’ve excavated a 5x10 area to a depth of 48+ inches. My plan was to mix what I’ve excavated (omitting the rocks and some of the sand), incorporating leaf compost which I have on hand, and possibly also adding some pine bark fines or other soil pep or non-manure compost, which are available locally by the trailer load.
I already know it was crazy to try to excavate this by hand, but what’s done is done. I now just hope for some guidance on preparing a mix that will give persimmons the best chance for success. My understanding is that they might prefer the ph a bit lower, and that they need a well-draining sandy loam rich in organic matter.
Thanks in advance for any tips or guidance for next steps from here.