I bought an Adenium Obesum (Desert Rose) plant two days ago (July 3rd) and I've kept it in the training pot. I haven't watered it since the soil was still a little moist when I got it. I noticed some white patches and some black dots on the bottom of the leaves, and after looking it up, came to the conclusion that those patches and dots may have been bugs, so I misted the undersides of the leaves with water and and liquid anti-fungal/ anti-bug spray for plants and gardens (my dad uses it on his Bonsai plants too, so I thought it would be okay). I then placed the plant in full sun- no shade at all- for several hours to dry off the water. When I came back, several leaves were turning a brown color and had wilted. I cut them off, thinking that it was leaf rot due to the water. Two days later (today, the 5th), I looked at the bottoms of the leaves again, and some of them are starting turn brown. I have not watered or repotted the plant at all. I also moved the plant into the shade of the porch, since the highs are anywhere from 100 degrees Fahrenheit to 120, but usually around 106 to 115. It's also very very sunny, but the next week is going to be mostly partly cloudy. I live in AZ and the temperature zone is 25-30. Hardiness is 9b. What am I doing wrong with my plant? What should I be doing instead? I worry that the temperatures might kill the plant and I really want to keep it alive. Please help.

In the past, I've only owned a succulent, but my mom accidentally killed it due to overwatering...

Thank you,
Hannalee

I would love to see an answer to this. I have the same thing going on, without the high temps. Mine aren't getting above high 80s.

Hello Han, not sure what caused the browning of your leaf, it may be some insect/bug damage as you said. But usually if I do have to treat a plant with something, I position them in part shade, to dry off. Or do the process before the hot sun hits the plant.

You also mentioned that you just got the plant two days ago, was it growing in a nursery or was it indoors? If it was in some shaded area before, it needs to acclimate to the outdoor heat and direct sun before exposing them head on. Leaves and caudex can get sunburnt, got to acclimate them slowly. Once acclimated it can take all the full sun it wants, but needs stepped up watering.

During summer time I treat my Adeniums like a typical tropical plant, daily watering here in my growing area since it is so hot and dry, we got no summer rainfall here, so it is a long 4 to 5 months very dry season. Temperatures in your area are much hotter than ours, so your plant will appreciate stepped up watering, but do it before the hot sun hits it. This plant is quite a toughie, I have read it can withstand up to 120F, which we have not reached here, so far we got into 112F here during our heat wave the other week.

I do not know what you mean by a training pot, but as long as that container has drainage holes and gritty, well draining media, it should be okay to do daily watering when temps are soaring quite high. It may slow down a bit in doing new leaves like most plants do when it is just excessively hot, but it will certainly keep the caudex rock hard and solid with all the moisture it will get from watering. I don't douse the leaves with water, I concentrate watering on the soil itself and I also spritz the caudex. It is just too dry anyways that in less than a minute the exposed caudex is immediately dry.

It will be different approach if your area is rainy, getting muggy and too humid, then you would need to give some intervals in watering. When Fall season comes around, got to scale down watering as temperatures start to go down. I start hiding my Adenium indoors for overwintering when overnight temps starts hitting 50F.