Does Your Avocado Have an A Flower or a B Flower?

By on October 10, 2013

An avocado tree in bloom. Those flowers have a gender-bending life.

Just when you think you’ve got all your fruit tree information down—along comes a new twist.

Avocado trees are divided into two camps by the kinds of flowers they have: A flowers and B flowers.

Does that sound like Thing 1 and Thing 2 from The Cat in the Hat? The avocado flowers act like cartoons too, with complicated openings and closings and sex changes. Mother Nature had a field day with this one!

Avocados are hermaphrodites (with “dichogamy” if you want to sound botanical)

Many plants are hermaphrodites, with male and female sexual organs, but avocados are unique because their sexual organs don’t function at the same time. UC Davis calls the avocado flowers “remarkable”.

The sexual organs of avocado flowers are active at different times of day (dichogamy).

A flowers” are female (receptive to pollen) in the morning and male (shedding pollen) in the afternoon.

B flowers” are male (shedding pollen) in the morning and female (receptive to pollen) in the afternoon.

For the most part, avocado cultivars have only A flowers or only B flowers. Production is best with cross-pollination between two cultivars, one with A flowers and one with B flowers. But the reality is, most cultivars of avocado seem to get better and better at producing fruits as they get older, another pollinator or not. If you live in a good avocado growing climate, there’s almost invariably another avocado tree in the neighborhood that will be your avocado tree’s buddy for many years.

“A flower” avocados

Little Cado (has A flowers and B flowers)

“B flower” avocados

Little Cado (has A flowers and B flowers)

Avocado flowers are like everyone else, happiest when the temps are in the 70s

Avocado flowers stick to their complex schedule of opening and closing as long as the daytime and nighttime temperatures are over 70F. If the temperature drops to 60F during bloom time they may not reproduce at all. A temperature of 65F, though, may confuse the flowers just enough that they gender bend and have both sets of sexual organs working simultaneously.

The avocado for containers

Little Cado is a dwarf avocado tree, maxing out at 8’-10’ tall, and is your best bet for container growing. Prune it to keep it smaller if you wish. This is the variety with both A and B flowers so you can get fruit with just one tree. You need to protect Little Cado when the temperatures drop to freezing or below.

How to choose your avocado trees

Jump over here to find out which kinds of avocados will thrive in your area. Then choose a combo of A and B trees for your garden or farm.

Watch our Growing Avocados video to find out how to plant, prune and harvest these versatile trees.

Photo by Cayobo available under a Creative Commons License Attribution 2.0

  Comments (17)


The Zutano says it’s sold out until August 2013.  Since it’s already November 2013, is this a typo?

Posted by Janet on Nov. 23, 2013 at 5:55:39 PM

Janet, Thanks for catching that! We meant 2014 and are changing that.

Posted by on Dec. 03, 2013 at 11:23:10 AM


I bought a Mexicola from Peaceful and wanted to find out if it was grafted or grown from seed. I heard if not grafted the tree will have NO fruit which defeats the purpose of my purchase.


Posted by paul on Jan. 08, 2014 at 9:38:24 AM

Hello Paul, yes all of our trees are grafted onto seedling rootstock, you should be able to see a little V-shaped scar on the trunk.  Our avocados are intended for fruit production. An ungrafted avocado will bear fruit eventually, but it will take longer and the tree will not have known characteristics like a cloned (propagated by grafting) cultivar such as Mexicola or Hass does.

Posted by on Jan. 15, 2014 at 9:04:59 AM


Hi, i am helping my San Francisco neighbors with their backyard, and they have an old avo tree. Is there any way to tell if it has a or b flowers? to my knowledge it has not produced fruit. Thanks!

Posted by Isao on Feb. 19, 2015 at 9:58:43 AM

Very difficult to tell whether or not it has A or B flowers. There are a couple of reasons why it does not produce fruit, either it does not have a pollinator or the temperatures are just too cold. If the temps drop below 60F during flowering, and if there are the appropriate pollinators, the tree will not make fruit.

Posted by Suzanne at Peaceful Valley on Feb. 19, 2015 at 10:32:50 AM


If you’re referring to A and B types, they are different because of time of the day that they flower, but all of them are first female then male (synchronously protogynous dichogamy). It appears as if they are like you described because of many flowers opening at the same stage

Posted by Nela on Mar. 08, 2015 at 12:56:38 PM


I planted seeds about 2 years ago.  The trees are doing good but have no flowers.  I live in Canada so they are indoor trees in winter.  How long do wait Thanks.

Posted by Kathy on Apr. 13, 2015 at 12:31:53 PM

I found one source that says it can take 7-15 years for these trees to start producing flowers. Here is the link, Hope this helps/

Posted by Suzanne at Peaceful Valley on Apr. 13, 2015 at 2:26:09 PM


We just bought a home with a large avocado tree but it does not fruit? What’s the story?

Posted by Jenny on Oct. 14, 2016 at 6:20:23 PM

Jenny, the tree probably does not have a pollinator. Do you know what kind of avocado tree it is?

Posted by Suzanne at on Oct. 17, 2016 at 10:32:03 AM


No, it was most likely planted from seed by the previous owner and it is big like 30ft tall big and there is just one.

Posted by Jenny on Oct. 17, 2016 at 10:36:43 AM

Jenny, without knowing what type of pollinator it might need it would just be a guessing game. If you find a Little Cado, it produces both A and B flowers. You might get lucky with that one.

Posted by Suzanne at on Oct. 17, 2016 at 10:39:51 AM


i have grown a small plant about 2 foot tall with leaves from a stone,how long will it be before i should see flowers…it is about 1 yr old now

Posted by roger on Oct. 19, 2016 at 5:41:31 AM

Roger, I have read that it can take from 4 years to 10 years for the tree to bear fruit. For fruit you will probably need a pollinator so hopefully you know what kind of avocado you grew the seedling from so you can get the right pollinator.

Posted by Suzanne at on Oct. 19, 2016 at 1:27:05 PM


Suzanne, i grew my tree from a avacado i bought in a supermarket, i have no clue about pollinators, or the type of fruit name, im in england so its spent most of its life indoors but in the summer i put it outside for a day or so and now its leaves are turning partly. brown and the insects have eaten holes into ithe leaves, but alas it is sttill sprouting new leaves, will it survive, shall i bring it back in now its getting cooler?

Posted by Roger on Oct. 20, 2016 at 4:33:23 AM

Roger, so really no way to know what type of pollinator you would need for your unknown avocado tree. I cannot say whether or not it will survive but you can bring it inside if the weather is getting cold.

Posted by Suzanne at on Oct. 25, 2016 at 10:46:10 AM

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