We planted some dwarf lime and lemon trees last April. The limes never or have not turned green and fall to the ground yellow. They don't seem ripe. Shouldn't they be green? The improved Meyer lemon, also dwarf, they are yellow but do not fall off the tree. Do we have to wait until they do or just pick them? What is the best fertilizer to use on these? I also have an orange tree, not dwarf. It has no fruit on it as of yet. Is this normal? Thanks.