I admit over-analyzing, by applying my analogy to nutrient availability in humans(with regards to why i think jujus do well where am at, apart from plenty sunny days). Will do this by bringing up blood sugar: at any given point, theres a fixed amount of blood sugar running through our veins. If we rapidly infuse 2 liters of sugarless IV fluid into a patient. The total amount of blood sugar running in patients veins will still be the same, BUT the concentration will be lower which affects availability to patient’s brain, and may then cause confusion, fainting, or even death. Jujus, like cacti, are native to dry conditions. Perpetually wet soils automatically result in decreased nutrient concentrations(in xerophyte terms), and the only way availability may be increased is by evaporation of water.
And taking it to an extreme scenario, you cant possibly get cacti to bear flowers or to bear fruit if you plant it close to a river(despite getting full sun and good aeration of its roots), simply because the medium it is growing on is too dilute, if not barren (again in xerophyte terms) Only way of ‘giving it a chance’ to achieve optimal concentration is to let the soil dry up, and just water again when soil gets too dry.
Also notable that in vegas summers, when i water trees, the moisture is limited to the finite amount i have released(which quickly evaporates in 110F weather)as the wet rootball is enveloped by a swathe of dry earth.
If you add a pound of NPK fertilizer to that rootball, that amount is pretty much contained within that volume of earth that is wet. But if you take that pound of NPK fert to use as amendment for that hypothetical cactus planted near a river, it is a literal ‘drop in the bucket’ since as soon as it is dissolved it will be fertilizing the entire volume of earth that is contiguously wet. Reaching far and wide.
Ok, enough of this nerdy hypothesis, lol!