Introduction
Understanding avocado flowers makes choosing among the many types of avocado trees much easier. Avocado trees have an unusual flowering system. Each flower contains both male and female parts, but those parts normally work at different times.
This timing divides cultivars into avocado type a and b groups. Knowing the difference can help when choosing varieties for pollination, climate, and harvest season.
How Avocado Flowers Work
What do avocado flowers look like? They are small, pale green to yellow-green flowers that grow in clusters. During avocado flowering, each flower opens twice.
There is no separate male avocado tree. If you have wondered, are there male and female avocado trees, the answer is no. The same flower has both reproductive parts. The avocado male and female phases simply occur at different times.
During the first flower opening, the flower functions as female and can receive pollen. It closes and later opens again in its male phase, when it releases pollen.
Weather matters. Temperature can change this schedule, so the A and B pattern is a useful guide rather than a perfect clock.
Learn more from UC Master Gardeners about the unique avocado flower.
Type A Avocado Trees
With type a avocado trees, flowers normally open as female in the morning of the first day. They close and reopen as male in the afternoon of the second day.
Common examples include Hass, Reed, Lamb Hass, and Pinkerton. Mexicola Grande is another cultivar often grown where greater cold tolerance is useful.
Is hass avocado type a or b? Hass is Type A. The same answer applies to hass avocado a or b and hass avocado type a or b searches. The popular Hass avocado tree is therefore a Type A cultivar.
What about reed avocado type a or b? Reed is also Type A. Reed avocados are known for their round fruit and green skin at maturity. Lamb Hass is another Type A choice.
Type B Avocado Trees
Type b avocado trees follow the opposite schedule. Their flowers normally open as female in the afternoon of the first day and reopen as male the next morning.
Well-known type b avocados include Bacon, Fuerte, Zutano, and Sir Prize. These are useful examples for an avocado types a and b list or avocado varieties chart. You can compare Bacon, Fuerte, and Sir Prize.
Fuerte avocados have green skin when mature and are a Mexican-Guatemalan hybrid. The many avocado type b varieties also show why there are more kinds of avocado trees than Hass alone.
Type A vs. Type B Avocado Trees: Key Differences
Avocado trees are classified as Type A or Type B based on when their flowers open in female and male phases. Understanding these differences can help you choose complementary varieties to encourage pollination and fruit production.
| Feature | Type A Avocado Trees | Type B Avocado Trees |
|---|---|---|
| First opening (female phase) | Morning of the first day | Afternoon of the first day |
| Female phase | Flowers can receive pollen | Flowers can receive pollen |
| Between openings | Closes until the following afternoon | Closes overnight |
| Second opening (male phase) | Afternoon of the second day | Morning of the second day |
| Male phase | Flowers release pollen | Flowers release pollen |
| Common varieties | Hass, Reed, Lamb Hass, Pinkerton, Gwen | Bacon, Fuerte, Zutano, Sir Prize, Ettinger |
| Pollination compatibility | May receive pollen from Type B flowers in the morning | May receive pollen from Type A flowers in the afternoon |
| Can one tree produce fruit? | Yes, depending on the cultivar and growing conditions | Yes, depending on the cultivar and growing conditions |
Why does this matter? Planting a Type A and a Type B avocado tree near each other may improve pollination and fruit set when their flowering periods overlap. However, a single avocado tree can also produce fruit. Successful pollination depends on factors such as temperature, pollinator activity, and the specific cultivars.
Do You Need Type A and Type B?
Planting type a and b avocado trees can provide pollen when flowers on another cultivar are receptive. This cross pollination can improve fruit set in some orchards and cultivar combinations.
However, you do not always need two avocado tree types to produce fruit. UC guidance notes that home trees can set fruit without a matching A and B pair. Weather can also create overlap between male and female phases.
So an avocado tree type a and b pairing can help, but it is not a guarantee of a larger crop. Bees, temperature, cultivar, tree health, and bloom overlap also matter.
If you want to grow avocados, choose varieties for your climate first. Our guide to choosing an avocado for your region can help.
Climate, Bloom, and Fruit Set
Avocado tree bloom timing changes with cultivar and climate. In Southern California, many cultivars flower during spring, but exact bloom season varies.
Cool weather can delay or change flower opening. This is why simply choosing type a and type B trees does not guarantee perfect overlap.
The flowers that are successfully pollinated may begin developing into avocado fruit, but only a small share of the huge number of flowers on a mature tree becomes mature fruit. UF/IFAS reports that less than 1% ultimately produce fruit.
Different varieties of avocados also vary in climate needs. If cold tolerant trees are important, compare cultivars instead of assuming A or B flower type predicts cold hardiness.
Florida avocado varieties can differ greatly from the cultivars commonly grown in California. UF/IFAS, for example, lists both A and B cultivars among Florida selections.
For broader care information, see our avocado growing guide, growing avocados video, and home avocado guide.
You can also browse our Citrus & Avocado collection. Independent growers such as greg alder may also discuss cultivar performance, but local Extension guidance is useful when comparing climate requirements.
Conclusion
The main difference among avocado types a and b is flower timing, not separate sexes. Type A cultivars such as the Hass variety and Reed normally begin their female phase in the morning. Type B cultivars such as Bacon and Fuerte begin their female phase in the afternoon.
Choosing complementary types may support pollination, but climate, bees, tree age, and cultivar all affect whether hass trees or other avocado tree types produce fruit.
8 comments
Valerie, I have read that starting avocados from seed can take as long as 13 years to produce fruit. Also there is no way to know if you have a tree that produces A or B flowers. I have been told you don’t need one of each but that you need to make sure that there are plenty of pollinators around to pollinate your tree.
I have an avacado that’s 11yrs old and never produced any fruit, inground and started from seed.
Doris, are you growing your tree in the ground or in a pot? Have you done a soil test so you know the tree’s nutrient levels? I would suggest adding an avocado fertilizer to your tree.
I have had my Little Cado avocado tree now for at least 10 yrs. Never flowered, never produced a single flower or fruit. Very healthy though. A & B. Supposedly no pollination required. Zone 9 so no problems with weather. Puzzling.
Susan, you can plant our Legume Oat Mix #1 or #2. https://www.groworganic.com/products/legume-oat-mix-1-raw-lb?pos=5&_sid=b7a831c7d&ss=r