Question
Aloha Kristina,

I have a Ficus Benjamina, the tree has many airial roots. I have repotted the plant form a deep pot into a more shallow pot. Most of the branches were cut back and also the roots were prunned. The tree recovered well, but after the foliage has grown back many of the new leafes turn yellow and fall off. The tree keeps procucing leafes but they all turn yellow. Do you know what might cause this?

Thank you for your help.

Answer
My guess is that it does not have enough nitrogen intake or the soil is too acidic for it.  When the leaves are yellow it mean a lack of nitrogen.  Acidic soil can cause "nitrogen lock" that means that they plant cannot take up nitrogen.  My best guess with out seeing it is that it is in a smaller pot therefore the ficus has already "eaten" all the nitrogen in the soil.  The best remedy for this is feed it a high nitrogen fertlizer at every watering.  My favorites are fish emulsion and sea weed extract.  Mix it about 1/2 of what the directions say if you use it every time you water.  If that does not clear it up it is acidic soil.  Add about a tablespoon of horticulture grade lime to a new soil mix and repot it.

I hope this helps you

Happy growing!
Kristina