First flowers are blooming.
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A male flower. When female, only a
single "stem" will stick up in the
center of the flower. |
Holiday is an "A" type avocado tree, which means its flowers follow a certain pattern of opening and closing that differs from "B" types. Common "A" types include Hass, Holiday, Reed, Mexicola, Pinkerton, and Gwen; common "B" types are Bacon, Fuerte, Kona Sharwil, and Zutano. All avocado flowers have both male and female organs, and shed and receive pollen at different times. An "A" type flower opens in the morning as a female flower, closes after a few hours, and then opens the next day in the afternoon as a male flower. A "B" type flower opens in the
afternoon of its first day as a female flower, closes, and then opens the next
morning as a male flower. Notice that when an "A" type is open as a female, a "B" type is also open as a male, which makes pollination much easier, and in fact commercial groves plant a few "B" types among their "A" types (Hass being the only avocado grown in large quantities in California). All avocado flowers close permanently after their second day, and either fall off or start the process of growing into a fruit.
This all apparently goes out the window in California. Avocados come from tropical regions in Latin America and the West Indies where things are much warmer; in the slightly cooler California climate, the flowers' internal clocks get thrown off a little and you will often find both male and female flowers open at the same time. For this reason avocado trees are considered semi self-fertile. I have seen male flowers open until midnight, and regularly find flowers of both sex open at the same time.
