I have a strong suspicion that Ilamas do not like alkaline soils. We had a seedling in a potting mix that sugar apple grew well in but it almost killed the Ilama. It recovered after being planted in acid sand. Also, I think they are more resiliant trees than sugar apple (at least in our acid "beach sand"). Over the years I have seen many people plant sugar apple here. They grow a few years and then die off. I know of an Ilama in Sebring that appears to be over 10 years old. It does not fruit much, but when it does the fruits are huge and symmetrical--about the size of a small grapefruit.
Thanx for the comments & comparisons of the requirements of sugar apples and ilamas, Galatians.
I mix my potting soil with 1/3 each milled sphagnum (acidic), humus (dug out of my azalea bed and prolly acidic, too), and coarse builders sand. Both sugar apples and ilama seedlngs planted in this mix have done well in smaller pot sizes. Meanwhile, I have sandy, well-draining soil in my yard here in Tampa.
Your comments, quoted above, have just about convinced me to go on and plant my large white-fleshed ilama out of its seven-gallon pot and into the ground.
Hopefully this larger ilama of mine will be able to withstand staying outside December thru February, unless we have some really cold weather.
Cheers!
Paul M.
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