I have a trumpet tree in a pot in my balcony. It has beautifully blossomed this spring and gave dozens of flowers. But since all the flowers fell down 1 month ago it has gotten worse and worse.
The leafs started loosing it's green color (see the pictures). Some of the bigger ones started dropping off.
It was then that I noticed some very small cobwebs and looking hard I started to see very tiny white spiders all over the tree. I proceeded to spray the whole tree with an insecticide I have that, according to the label, is appropriate against spider mites. It didn't get better but it also didn't get worse.
Yesterday I was watering the plant and it lost 5 or 6 leafs just for a little shake of the pot. I noticed again the spiders, this time many more than before, so I sprayed them again. This morning I found 15 more leafs on the ground.
Could this spiders be responsible for this? How can i get rid of them? It is also worth mentioning that I usually water the plan with hard tap water, is this bad as well?