Q: I’ve grown an olive tree in a large patio container for eight years. I bring it into the garage when it gets below 20 degrees in winter. For the last two years it has been loaded with blooms in spring, but all the blooms fall off and there is no fruit.

A: I admire your persistence! The flower drop sounds like there’s a lack of pollination. Olive flowers are self-pollinating, so you don’t need a different variety. It’s possible for heavy spring rain or an unexpectedly cold night could damage the flowers so much that pollen is not transferred. The technique that I use for tomato blooms might work for you next spring: tap the flowering twigs a couple of times each day with a pencil or a chopstick. This will help the pollen release and get where it needs to be.