I have a one-year old dwarf Meyer lemon tree that appears to be doing very well. Last year, I had a three or four lemons although they never turned completely yellow. This year, I have at least 20 in various stages of growth. The leaves are not as dark-green as they were last year. What can I use in conjunction with the organic citrus fertilize I use monthly to make the leaves a darker green or does it matter?

I also missed my window of opportunity for re-potting. Should I wait until the fall to do this and what kind of potting soil would you recommend?