I had purchased a guava tree (in vase) a month ago and from the beginning (some leaves had problems when I got the tree), some red spots or areas appeared on the leaves. After a while some of them dried and dropped off. What is the problem and how I can cure it?
I water it every three days, it is near the window and has 5 hours of sunlight every day, the temperature is about 20 degrees Celsius.
Your plant may have spider mites. Check on the underside of the leaves for what looks like small grains of salt. If you see them then apply soap and water at a ratio of 5ml to one litre three times at five to seven day intervals.
The light and dark parts on the leaves indicate that this plant has a nutrient deficiency. As this site indicates:
Guava trees are susceptible to iron deficiency under alkaline and high pH soil conditions (e.g., rockland soils, calcareous sands)
You should apply iron sulfate or a chelated micronutrient mix up to twice a year according to the instructions on the fertilizer label.
Repotting with a soil mix that has some compost or other organic matter should help too. The plant is potted in a peat based mix that works well for growers but does not have the same ability to hold micro nutrients over time as soil does due to the lack of clay.
