I have two orange trees that were planted 12 years ago. They bore beautiful fruit until four years ago, when my gardener pruned them rather severely. Since that pruning, no more fruit at all. But the trees appear healthy -- very green, with few yellowing leaves. Please advise as to how we can get them to bear fruit again.
For answers on if or how gardeners can revive a badly pruned citrus tree, we turned to Frank McDonough, botanist at the Los Angeles County Arboretum and Botanic Garden in Arcadia.
McDonough's first step was to ask Berlin more questions: How do you fertilize your trees? What type of fertilizer, how much and how many times per year? How frequently do you water your tree, and for how many minutes? How many hours of direct sun do these trees receive?
With more information in hand, McDonough offered this response to Berlin:
From what you’ve told me, I am surprised your citrus are still alive. Irrigating citrus three times a day is more than unnecessary. It's highly deleterious. Waterlogged soil causes citrus blooms and leaves to fall off of the tree; no blooms mean no fruit. Soil watered that frequently also is ideal for the root rot organism known as Phytophthora.