Surplus of fertilizers for a tropical plant
Let’s consider, that you have started to fertilize you plant in due time - however, have gone too far with a doze. The result of such overdose - a plant “chokes” with the offered amount of fertilizers and gets the real food poisoning.
Symptoms: leaves wither, become grayish, and sometimes blacken; the top of a plant (growing point) dries up and dies off. The plant stops to develop. Overdose of nitrogen (urea) in cold weather is especially dangerous - roots of a plant will be burnt.
The help: get the land clod from a pot, wash out roots from a soil (as soon, as possible), and transplant it in a fresh substratum without fertilizers. If painless washout of soil from roots is impossible - at least, wash out land clod under running water. Let the water flow down completely.
If “poisoning” has not gone too far - the plant will start to come to the senses gradually, but very slowly; renewal process takes weeks, and even months.