How can I encourage my Citrus trees to bear fruit?

[dylanalexander55]

I have three young trees (lemon, Lime, and Orange) outside in my yeard. The lime has had many blooms, but no fruit has made it past pea size. The lemon has only had 3 blossoms in 3 years. The orange has not had any blossoms since I first planted it. I fertilize every ~3 months with a citrus fertilizer. How can I encourage fruit production? Also am interested in remedies for leaf miners.