Re houseplants: most spoiled foliage is caused by physiological issues, over/under-watering, oedema, nutritional toxicities/ deficiencies, light levels, ...... with subsequent populations of fungi acting as opportunists as opposed to acting as causal agents. In this thread, oedema, a physiological disorder, is the main actor. Dead animals don't cause vultures, but they do provide a reason for vultures to congregate. IOW, lesions caused by physiological disorder often provide the consistently moist conditions for a period lasting long enough to ensure incubation and germination of fungal spores. This isn't to say that fungal conditions do not commonly appear in plants as pioneer pathogens, only that evidence of physiological disorder is far more common than direct evidence of pioneer populations of fungi. Plant pathologists often describe the disease process using a 4-sided figure called the disease tetrahedron (think “pyramid – 3 sides + the bottom/ base”). Each side of the tetrahedron represents an essential part of the infection process. There must simultaneously be a virulent pathogen (capable of infecting the plant) that is genetically capable of recognizing its host. Either the environment must be conducive to the development of the pathogen, or the pathogen must be able to stress/weaken the plant. The 4th requirement is the time required for diseases to develop and spread. Whenever conditions are such that any one (or more) of the 4 requirements is missing from the equation, there is no immediate threat. Since the best medicines are prophylactic, the grower who makes sure plants are healthy and not stressed is ahead of the game. Biotic diseases are better able to overcome the natural defenses of plants weakened by stress that occurs when the plant is forced to deal with cultural conditions near, at, or beyond the limits the plant is genetically programmed to deal with. Al

Without a better description of the yellowing, it is hard to tell what the cause is, whether it is water related, a nutrient deficiency, a disease, graft failure, or what. Since you brought up spreading calcium sulphate on the soil, whatever gave you this idea may point towards your problem. It could be an iron deficiency. Did your early leaves have a good green color, then later growth came out yellowish, with each shot of new growth getting yellower, maybe to the point that some new leaves were almost white? Do the yellow leaves have a tendency to still have green veins? I think peaches and nectarines are more sensitive to this than some other common plants and trees. Soils found in dry climates, former lakebeds, or from certain parent materials tend to be alkaline and sometimes salty. Frequently, you will find your soil pH on alkaline soils runs between 7 and 8.5. As you go above 8.5 it gets very difficult to raise our common garden plants. To help reduce the pH and help free up the salts so they can be washed from the soil, calcium sulphate, commonly known as gypsum (found in sheetrock) is used. The sulphur reduces the pH, the calcium replaces the excess salts in the soil and allows them to wash out. This can be a long term process and can take a lot of gypsum over time if your soil has a large content of minerals promoting alkalinity. At pH around 8 or below, I find that most plants will do well although they may need some periodic help. What happens in alkaline soils is that iron is tied up and mineralized so that it is unavailable to the plants, even though it is often plentiful in the soil. When you lower the pH, the iron becomes available again. Rather than trying to convert your soil (you could use gypsum for modest adjustments), I would suggest you use iron sulphate, which lowers the pH temporaily and at the same time provides soluble iron available to the plants. New growth will begin coming out green again, although the yellowed leaves will never recover. Iron sulphate can be purchased in 25-50 lb. bags at fertilizer dealers, or as Ironite in your garden center. Spread a cup or two lightly around the base of the tree and several feet out, a rate similar to what you would use to put fertilizer on a lawn. DON'T get the iron sulphate on cement, rock, or other hard surfaces as it will almost permanently stain them rust colored when they get wet. (I've had this problem) You can also spray the tree with iron chelate to feed the leaves directly and get quicker results, but you have to keep spraying every couple weeks. To treat a tree in trouble, you might want to spray the tree once or twice and spread iron sulphate on the ground, then in the future, just spread some iron sulphate every year or two at the first sign of leaves starting to yellow. Before trying this, try to identify the cause. If your soils are alkaline, this won't hurt periodically, but it may be unnecessary if something else is...

Peppers need similar fertilizer to what is used for tomatoes. I use synthetics with a 3- 1 -2 proportion. For example MG 24- 8-18 liquid. I think it has magnesium and sulfur too, which peppers demand. I am sure there are some other brands and types. The one I mentioned is pretty much all-purpose.

I received mine when it was approximately 8" as well. I keep it in full sun since I live up North in zone 7B. The plant has not stopped flowering and sprouting leaves. I also have 6 babies growing. Whenever I see a pod that's about to burst, I keeo an eye out for the seeds, I then just tuck them in the soil about 1/2"down and about 1 -2 weeks later my babies sprout. I have also heard of people putting a mesh bad around the pods to catch the seeds since they do tend to "fly" rather far from the tree. I winter it indoors and still have beautiful leaves and some flowering, but I have never not had a flower. Good luck.