Hello! I agree, in the initial inspection of the photo it appears to be burn of some kind. That could be sunlight reflecting and/ or pesticide - especially with 2 applications back to back, hard to say. BUT, what you should be most concerned with are how the new leaves look, more so than the old. It is natural for your leaves to yellow and fall off, especially the oldest ones. But if you feel it's doing it at an alarming rate, then I would say it could be too much water. (or if you saw the new ones yellowing or falling) I notice you have saucers under your pots too, that will hold excess water you don't want. The soil in the little seedling looks very wet - had you just watered? Don't be afraid to check your soil, check your roots. Is your plant root bound? Is your soil well draining? What are your temps like right now? At this point it's hard to say too much or not enough water, but you can find out quickly by checking your soil. Your leaves are a tad drooped , so I would say not enough, and your leaves look really good other then the droop & the burn spots. The temporary move could be a big factor like the others have mentioned. Check them out & let us know & we can go from there!

The first defoliation was most likely a function of the change in light between where it was sited at school and the lower light area where it is/was at home. It's very possible that the crispy leaf tips/margins are being caused by over-watering, a high level of salts in the soil (from fertilizer and dissolved solids in your tap water), or a combination of both. If your plant is wilting when you can still detect moisture in the soil, it's almost certain that root function is impaired, and the plant 'perking up' as evening approaches supports that thought. Again, this may be the result of an overly water-retentive soil and the lack of air in the root zone that comes with it, or a high level of dissolved solids (salts) in the soil, or both. Even the recurring insect infestation can be resultant of a suppressed metabolism due to poor root health. The fix when your plant wilts while the soil is still moist is less water, not more, and a flushing of the soil to remove excess salts that may be inhibiting water uptake. A high level of salts in the soil can do the same thing to plants that salt does to cured meats, like ham, bacon, summer sausage ..... When the level of salts in the soil is higher than the level of salts in plant or animal cells (meat), the salt actually pulls moisture from cells. When this condition is severe, a condition called plasmolysis can result as cells collapse and plasma is torn from cell walls. Commonly, we call it fertilizer burn. Al PS - it's much more important to shade the container than the foliage. A light colored cache pot filled with an absorbent material you can keep moist (between the 2 pots) or a pot-in-pot arrangement with the outside pot being white or a light color would probably go a long way toward keeping root temps out of the danger zone.

Most of them are in the ground. The one with the most severe symptoms is in the ground in a moist planter with pretty much full shade, but with a little bit of late afternoon sun. Another one in a pot also has the symptoms and had been kept in the same area, but we just moved it out more into the sun. The ones around our pool, in pretty much full sun, are doing much better. I'm going to make up a batch of the insecticidal soap spray (I have a good recipe) and treat them all, as well as the whole planter. Plus, I have chinch bugs in my lawn, so they will get a dose as well! Thanks for the help.....Dean

hi hubbard. thrips may be a problem to your plumeria. they attack as or after new growth appears. they are tiny pests, and you dont see damage they do till after the fact. they are sucking insects, and suck the leaves dry when they are young. as the leaves grow, they will start to curl inwords. at this time, it is to late to solve the problem, as they are not around any more. as your plumeria comes out of dormancy, and about one quarter to one third of your tree is covered with leaves, use a product by "bayer". it is called rose fertilizer and insect control. you can get it at home depot. it comes in a blue jug by the rose chemical products. follow directions, as to the amount you may need to give, as to the size of your tree. it contains a systemic which will stay in the tree for about 45 days. this will control all your pest problems, including spider mites and aphids. hope this helps!