Lemon fruit drop can happen for variety of reasons
Question: Our Meyer lime is full of blooms. In previous years, it has yielded lots of fruit. However, last year, the blooms were abundant, but all of the bloom fell off, and we had a crop of one lime. What happened?
This is probably a Meyer lemon. It can be difficult to say exactly, but we can start to narrow it down. The major culprits are irrigation, late-spring freezes and poor pollination.
Meyer lemon is self-pollinating, which means it can pollinate itself. However, there seems to be some evidence that bees will increase fruit set and the number of fruit produced. Check your fruit and see if you have lots of seeds. If you do, then a lack of pollination was probably not the problem. If there were just a couple of seeds, then maybe the tree needs access to more bee activity.
If we have a late spring freeze, then it is possible the flowers were killed after pollination, resulting in poor fruit set. This can happen some years. Try to restrict cold winter and late-spring winds from directly contacting the tree. Use a wind barrier after or during bloom, but don’t restrict bee activity.
If the tree is not being watered evenly, a very dry and wet cycle or even one very dry period during or slightly after bloom can cause fruit drop.
Bob Morris is a professor emeritus in horticulture with the University of Nevada and can be reached at extremehort@aol.com. Visit his blog at xtremehorticulture.blogspot.com.