Just to let you know again, spider mites can't be seen by your normal eyesight. They're microscopic! University of Florida describes them as 1/50th inch long. The female is 0.4 millimeters. You can't "see" spider mites, literally! But just because you cannot see them with your plain eyeballs, doesn't mean it's not on your plant. Your leaves show the most common spider mite symptom. I would advise you not to ignore the very high likelihood of spider mites on your plant. Your organocide will only kill adult bugs on contact but any eggs that are on your plant will not be affected. You'll have to keep spraying until you take down every last bug going through their adult phase

A photo would really help. Words alone can mean very different things to different folks, But based on the info so far I'd be questioning the magnesium and the azomite additions. Such additions are unusual unless based on a professional soil test and could easily create problems. Dave

We need to know all of the following in order to make any kind of meaningful comments :-) your geographic location - state and largest big city what kind of tree when was it planted (if you know) usual summer weather and watering practices and as many clear photos as you can manage...the tree as a whole, shots of the branches with dead leaves and close ups of the leaves (front and back) as well. Fwiw, some trees will have assorted leaves dry and brown a bit in summer and also many that will tend to hold their leaves very late into the season and even through winter. Does not necessarily mean the tree is sick or ailing.

Suzanne - are you using a tell to monitor moisture levels deep in the pot instead of a finger stuck in the top inch or so of the medium? Did you flush the soil to 'reset' the level of dissolved solids (salts) in the medium? Are you fertilizing regularly, based on the number of times you've watered to beyond the point of complete soil saturation? We should have some idea of where you live, as that will be taken into consideration when giving advice, and you'll get advice less general. Important to plants is their LCP, 'light compensation point'. Plants are at their LCP when they are creating as much food (plants make their own food during photosynthesis) as they are using/ burning during respiration. A plant can only grow when it is making more food than it is using. If they are incapable of functioning well enough to reach their LCP, the trend is toward loss of viability, so the trend must be turned around before it exhausts all energy reserves and dies. If your plant is not growing, it is very near it's LCP or on the wrong side of it. Giving it more light and favorable temps, monitoring moisture levels to avoid over-watering, and fertilizing on a regular basis with an appropriate fertilizer is where you'll gain the most traction, but sometimes a pathogen or insect herbivory undoes your good work. More later. I'll wait to see what your reply is, or if you reply. Looks like the weatherman was wrong today and I have some weather-related chores I need to attend to. Al