In the spring you see flowers on your avocado tree that soon become green fruitlets. Wonderful! Your tree is making avocados! Then they start dropping.
What did you do wrong? Why is this happening? When will it end? How many are going to fall?
Why avocados drop:
Natural self thinning
Most often, young avocados are shed by a tree because the tree has set more fruit than it can handle. It is self regulating; it is self thinning its crop load. There is nothing you can do to stop it, and you wouldn’t even want to try.
I tagged a branch on my Lamb avocado tree on June 13 and counted the avocados set on that one small branch: 43.
There is no way that a branch that is only as thick as my finger can carry 43 mature avocados. So the tree got rid of most of those tiny fruitlets until it had only seven left when I checked it on July 2.
Here on July 22, there remain five avocados.
That’s more manageable.
Incomplete pollination
Another reason that avocado trees drop some of their fruit is that the fruit hadn’t been properly pollinated or fertilized. Sometimes you can see this when you cut into a dropped avocado and find that it has a dark-colored, aborted seed inside. (Not to say that all avocados without healthy seeds inside are abcised though.)
There is also the chance that the fruit would have had a better chance developing if it had been cross-pollinated. Some studies show that avocados which have been cross-pollinated are more likely to fully develop until maturity (see one from Israel and one from South Africa).
On my Pinkerton avocado tree this year I have gotten both more fruitset and less fruit drop than in years past. I can’t say for sure what this is due to, but the only variable that has changed around the tree is that this is the first year that it has had significant cross-pollination opportunities.
Last year I planted an Ettinger avocado tree next to the Pinkerton. This spring, both bloomed and I watched bees cross between the trees throughout the day, every day.
I tagged a branch on the Pinkerton tree on June 13. At that time, it held four avocados. On July 2, it still held four avocados. Today, it continues to hold four avocados.
Again, I don’t know that this has anything to do with cross-pollination, but I suspect it.
Heat or water stress
Young avocados are far more likely to be dropped from a tree that is stressed compared to older, bigger avocados. For example, in early July of 2018 we had a blazing heat wave in Southern California. My yard reached over 115 degrees. I had hundreds of avocados on my trees that had just started growing. My trees shed most of those small avocados over the next few weeks due to the heat stress. However, none of the mature fruit dropped. Not a single mature avocado dropped from any of my trees.
We must be very attentive to watering (and possibly using other heat mitigation techniques) through any heat waves during the late spring or early summer when our avocados are young and small in order to prevent or at least minimize drop.
When avocados drop
But after July, most avocado varieties stop dropping fruit — as long as they’re not severely stressed from heat or lack of water. For Hass in particular, you might see a few avocados still dropping in early August, but by mid August for sure you should no longer see fruit drop in numbers.
Some late-blooming varieties continue to drop fruit a little later, as can be expected. I’ve always continued to have some drop on Lamb and Reed through August. I’ll even get a few fruit dropping in early September. By mid-September, fruit drop should cease on these varieties.
So in general, you can count your predicted harvest for the following year in the late summer, around August or September.
(One side note to this is the fruit drop that occurs in the second spring on some avocado varieties with summer harvest seasons. Varieties such as Reed, Lamb, and Holiday often start to drop a few fruit in the second spring when they’re almost mature. I don’t know what causes this or how to prevent it. Luckily, the fruit is usually bland but still edible — so not a total loss to a backyard grower.)
How many avocados drop
I’m aware of no simple answer as to what proportion of tiny fruit set in the spring will drop before the August/September cessation. I’ve seen trees drop almost none and others drop hundreds, all in my own yard and given the same care.
Others have observed the same. For instance, in one study of Hass trees growing in Irvine, California it was noted that in 1995 only 12 percent of fruit that set remained on the trees whereas in the following year 64 percent remained.
Moreover, I’ve seen different branches on the same tree drop very different percentages. Remember my Pinkerton tree whose tagged branch held four avocados from June 13 until today? Well, another branch on that same tree had five avocados on June 13 but only one today:
(I still suspect the tree’s fruitset and retention has been helped by cross-pollination from the Ettinger because of the amount of fruit remaining on the tree overall.)
Minimizing avocado fruit drop
What can we do to keep as much fruit on our avocado trees as they can manage? What surely helps is to never allow a tree to stress from heat or lack of water. Anything else?
— Growers and researchers have looked into pruning techniques but I’m aware of no consistent results found (see “Factors Affecting Fruit Set / Early Fruit Drop in Avocado” by Carol Lovatt).
— And they have looked into the influence of fertilizer applications but haven’t found clear results that I’m aware of there either (see here, for example).
— Finally, if you’re experiencing a lot of fruit drop on a healthy, unstressed tree, you might consider providing for cross-pollination in the future. There are various ways to do this, including planting an adjacent tree of the opposite flower type, using a potted pollenizer tree, and grafting in a pollenizer branch.
It’s late July . . . how many avocados will our trees still hold in August and September — and therefore probably all the way until eating time? Let’s keep them hanging!
Walk through my yard with me in a video version of this post:
All of my Yard Posts about avocados and other topics are listed HERE
Loved your video on this topic on YouTube. My Reed is 3rd year in the ground. Shaped like a Christmas tree about 5 ft tall. This year it seemed like every flowers set fruit. I removed roughly about ~200 little baby fruits early on Right now there are about 6 on it about the size of golf ball. I hope the tree will hold on to it until July 2022.
Come on big money!
Greg,
I have a wurtz avocado tree that dropped most of its fruit this season but 2. Wondering if I need a pollinator tree. I used to have a Lamb (dwarf?) Hass. Will that work as a cross-pollinator, and in North SD county, do you know where I can find one? Thanks
Hi James,
I don’t know much about Wurtz, as I don’t grow it myself. But I do know a lone Wurtz tree that is very productive. Pollenizers never hurt though.
Wurtz is said to be an A flower, so rather than Lamb I’d try a B type.
My avacado slick skinned. Usually large seed. In last 5 years 2 times all the fruit was a little shorter than my little finger. You could eat them skin and all including seed Husband wouldn’t eat them but I would. Other 3 years all fruit was normal. This is the small fruit year. Why??
Why was my tree full of fruit then they all disappeared. Is it because rats eat them or other reasons. Very disappointing
Another excellent video. My Pinkerton and Holiday hold onto fruit better than my Hass or Bacon. My 9 foot Stewart dropped all but three….
Very interesting article on fruit drop. This past year my Nabal tree, for first time yielded 22 large, softball size avocados up to 17oz. This year, (it’s late July) I’m only counting 8 or nine golf all size fruit. The Hass and Fuerte are loaded. Would this be normal for the Nabal? This time last year the tree had uncountable numbers of fruitlets until the 22 that developed. I don’t know if this is a normal cycle for Nabal or if I’m doing something wrong.
In Point Loma (the wooded area there are lots of animals) rats, opossum, raccoon and skunk. Is there a way to stop whatever it is from stealing, eating the mature fruit at night? Thanks, Denny Berg
Hi Denny,
Your fluctuating production on the Nabal sounds normal. I’d expect another heavier year next year.
That’s tough about the animal competition. Other than controlling the animals themselves, I’ve heard of some people having luck with wrapping mature avocados in plastic bags with the bottom cut out for airflow. I’ve never tried this myself though. If you try it, let me know if it works for you.
Thanks Greg. I’m trying to think of something to put around the trunk to block climbers. I have a friend who uses tea tree oil for fruit in his back yard. I have time and will let you know if I come up with something. The Hass tree still has about 25 avocados on it and hundreds of fruitlets. We have been enjoying them since last November but never thought we could pick fruit while new ones are approaching golf ball size. Is this normal?
Hi Denny,
That’s totally normal for varieties like Hass and others whose harvest seasons last beyond spring. It’s especially common in your area — close to the beach — because the mature fruit hangs on the tree much longer compared to inland.
Speaking of November, I’ve eaten delicious Hass from trees near the ocean in Carpinteria in their second November. In other words, the mature avocados had hung on the tree all the way through summer into fall and still tasted good. Close to the beach, a Hass tree can have palatable to excellent fruit on it year round.
So my avacato tree is over 40 feet tall. I can’t reach the fruit. Should top it at back to 12 – 15 feet. Maybe more fruit will mature if it is not supporting so much tree?
Hi Stephen,
I have a hard time picking fruit higher than about twenty feet up so I like to keep avocado trees below that. Topping your tree might be a good idea for you too.
I don’t think your tree will produce more fruit after topping (unless it is not being watered well now), but you sure will be able to pick more of whatever fruit it produces.
Do you guys spray micronutrients like boron,zinc on your avo trees? We are trying that down here in kenya.we do commercial avo farming for export markets. Also pruning is important
We have successfully tried clear plastic 1lb strawberry clam shells when we found several avocados chewed on by possum. It worked very well, no damage to hanging fruit and kept all critters away for months.
Hey, Paul. I don’t think Possums have strong enough jaws and teeth to chew on a non-ripened avocado. Citrus and tomatoes are more their speed. Speaking from frustrating personal experience, trust me. More than likely, rodents are the culprits. Rats and/or squirrels. Yuck, I know. Also from personal experience.
It’s definitely rats at night and squirrels in the day. I have cameras all over my yard and I know what critter is damaging my fruit trees and veggies. I actually feed opossums on my back wall with watermelon and cat food. I put it in unset rat trap cages as the rats are too wary to go in. I recently put out contrapest contraception bait in a station for the rats. Hope it makes a difference. The clam shells and upside down cups with a slit on side do work to protect fruit. I cover all the ones I can reach
Thanks, Paul, Eduardo, and Bita. We might need to get a post written about protecting avocados on the tree because so many people struggle with this. It’s especially heartbreaking when you have a young tree with only a few avocados on it and you lose them or they get damaged by critters.
I form a cone of aluminum foil on a branch with fruit (also works for figs, etc.) and stuff it with citronella pellets. The citronella smell overpowers the smell of the fruit and rats and birds doing like the foil. Voila!
Great article and information , Greg!
Great post. My Fuerte typically sheds 1/2 to 2/3 of its tiny fruit, and still produces quite a bit. Two years ago, I was checked out mentally when a big heat wave hit, and I lost pretty much over 95% of the fruit. Figuring for squirrel damage, I think I got 5-10 avocados out of it all season, where it typically produces 80-100 easy. Now I watch the weather forecast, and if I see 90s coming, I do a pre-soak. I have sandy soil and the tree is on a slight downslope, so no concern of waterlogging it. This year I also increased my sprinkler time for that zone in my yard, and the Fuerte is very happy… along with all the seedlings I have growing in pots under its canopy. 😀
Hi Greg. Thanks for the useful & informative posts. I have a 4 or 5 year Hass avocado tree. I got 3 avocados last year & none this year. Even the flowers did not look good this year. Most of them looked burned at the tip of them. The tree is about 7’ tall & looks very healthy. For cross pollination I planted a Fuerte avocado tree next to it last year but this spring it did not produced any flowers, which of course I was not expecting it to due to its age. What am I doing wrong? By the way, I live in the East Bay of the Bay Area.
Hi Zahra,
It actually doesn’t sound like you’re doing anything wrong. I bet that if you give your trees another year (or two at the most) they’ll be working together and producing. The first Hass tree that I have in my current yard didn’t produce anything until it was over ten feet tall, but then it came in with a big crop.
By the way, I’m guessing that the flowers that “looked burned at the tip” were just flowers that didn’t get pollinated. Such flowers turn brown and wither and then fall, naturally.
Did you see many bees visiting the flowers? You might work this summer to increase bee numbers in your yard. See my post on providing food for bees: https://gregalder.com/yardposts/growing-a-bee-garden/
We have a beautiful healthy 5-year-old hass avocado tree and all of a sudden in the last 2 weeks it’s shedding all its leaves and it looks sickly. We’re giving it plenty of water and fertilizer so we’re not sure what’s going on. May I send you some pictures? We appreciate your help
Hi Sharlyn,
You can share links to pictures by posting the pictures on a sharing platform like Google Drive or Imgur.
If the tree has few leaves, certainly reduce the watering and fertilizing right now. Extra water and fertilizer might seem like it could help a sick tree but it could actually harm it. You can easily rot the roots of avocado trees that have few leaves because leaves are responsible for drawing the water out of the ground, into the roots, and up the tree. With few leaves, the water mostly sits in the soil “unused”.
Can small home gardeners grow any of the avocados in the yard? I live in the Monterey Bay area and can only find the Haas varieties and a Sir Prize at the nurseries. Some said the Sir Prize won’t do well in my area. However, I did plant a Sir Prize recently. I’m trying to find a GEM, but it seems it’s only available in Southern California. Is it our temperature that only certain varieties can grow in my area? When they say they won’t do well here, does it mean low fruit production or because of other issues?
Hi Laura,
It all depends on what you mean by “small” and how much pruning work you want to do, but see details about growing an avocado tree in a small yard in this post: https://gregalder.com/yardposts/can-you-grow-an-avocado-tree-in-a-small-yard-space/
Avocado varieties come in two types according to their flowering behavior: A and B. In general, A types are more consistently productive in any single location, and they’re also productive in a broader range of locations (climates). As you mentioned, this is related to temperature. I should write a full post about this, but if you look at these two posts you’ll find a few details on the topic:
https://gregalder.com/yardposts/avocado-varieties-for-year-round-harvest/
https://gregalder.com/yardposts/whats-the-best-kind-of-avocado-to-grow/
You’ll really only know if Sir-Prize (a B type) will produce in your yard after you grow it there. So time will tell. But in short, such B types need higher average temperatures during flowering compared to A types in order to fruit well.
You’re right about GEM trees being only available in Southern California, except for a nursery or two up in the Bay Area that occasionally buys trees from a nursery in Southern California and then resells them at a premium.
Great timing and very helpful information! I’ve been wondering about my avocado dropping fruit. I think it’s a Fuerte and has hundreds of fruit on it. The bees loved it! I almost thought there was a hive in the tree there were so many bees for about a month. Unfortunately my tangelo and lemon lost a lot of flowers with the winds here. Hopefully they will do better next season.
Thank you for sharing!
My GEM dropped quite a few pollinated, golf ball+-sized fruit in early August here in Irvine, where the weather has been excellent. At the same time, the tree putting on a big flush of leaves. Still plenty of fruit hanging in there. Perhaps the tree is simply recalculating its energy budget and deciding to invest more in vegetative growth?
Hi Greg–I’m using your “Watering Avocados in Calfornia” guide and so far, so good.
However, I’m wondering if the watering suggestions might be augmented by the
global warming (or hotter/longer than usual) experience we all know about. I know I
can do longer waterings, but am wondering if you’ve decided to use a multiplier to
your derived numbers based on changing weather conditions.
Hi Steve,
Your notion of watering based on changing weather conditions is the best one. That is what we should all do. And the weather is sometimes hotter than the historical average but not always; for example, in my location, this summer the weather has been cooler than average and, in fact, two days ago was a daily record low maximum of only 71 degrees. Because of this, I skipped an irrigation that I would have normally given my avocado trees.
I will definitely update the table in the avocado watering post if I find new data that I can use for historical average ET rates for Southern California. I haven’t seen any yet. If you do and I’ve missed it, please let me know.
How do you know when its time to take away an Avocado trees support?
Hi Monty,
That’s not an easy question to answer. Before removing stakes on an avocado tree, I usually cut away some of the ties or replace them with looser ones for a time. This gives me a chance to see if the tree will remain tough and erect without the support it has had. Sometimes a tree appears ready only to slouch over in some wind the day after you’ve removed the stake.
Some signs that you can reduce support include taper in the trunk (the base will be obviously thicker compared to higher up) and a generally balanced canopy shape (if one side is much larger and heavier than the other, the tree’s probably not going to stand on its own for long).
If you haven’t seen this post and the video within it, you might get some extra good ideas here: https://gregalder.com/yardposts/training-young-avocado-trees/
Dea Mr. Alder, I was given your name by Four Winds Growers. I sent them pictures of my 12 year old little cado tree. My letter stated that all of the baby avocados fell this last Spring. Only a few survived last year. Previously I would get at least 100 avocados a year. Four Winds Growers told me my tree looked incredibly happy and to keep doing what I was doing. They talked about temperature and wind. I am hoping you can help me get my avocado tree producing again.r
Hi John,
Sorry to hear your tree isn’t producing. Let’s think about what has changed around the tree. If it produced well in the past, and it still looks very healthy right now, then some possible problems are that it just didn’t bloom much this spring; another avocado tree in your yard or in a neighbor’s yard has been removed (and that tree had been helping to pollenize yours); there was a heat event that stressed the tree this last spring. Any of those sound like possibilities?
Thank you Greg for responding to my email. I cannot think of any changes that have occurred around my little cado tree. The recent blooms have been excellent – lots of busy honey bees – with many baby avocados ( the little cado self pollinates ). I am aware that this variety commonly has a production spike every other year but I have had two bad years in a row. I did have an excellent conversation with U C Master Gardeners of Stanislaus County. One of their thoughts was that the roots had reached my lawn area and possibly the tree was getting too much nitrogen. Is that a possibility? At this point I shall wait and see what happens next Spring. Hopefully I’ll get a good set. Again, thank you Greg for responding to my email.
Hi John,
It is unusual for a tree to have two low-production years in a row but not unheard of. One low year is normal, two low years is unusual, three low years is worrisome. If you don’t get lots of fruitset next spring, then we’ve got a mystery on our hands that deserve deeper exploration.
High nitrogen could be a factor, but I doubt it is the sole factor. Although there has been some research showing that both extremely high and extremely low nitrogen levels reduce yield, neither results in no crop.
For more on this, see page six of “Reasons for Low Yields of Avocados”: http://avocadosource.com/CAS_Yearbooks/CAS_51_1967/CAS_1967_PG_161-172.pdf
And see this fertilizer experiment: http://avocadosource.com/cas_yearbooks/cas_42_1958/cas_1958_pg_111-113.pdf
Also see this more recent nitrogen fertilizer trial: http://avocadosource.com/CAS_Yearbooks/CAS_80_1996/CAS_1996_PG_085-098.pdf
Greg
I just discovered your site and found it super informative. Thanks for this incredible resource.
I have a bit of an unusual question for you. I’m in San Francisco out by Ocean Beach. I make my own compost from kitchen fruit and veg scraps along with garden trimmings. A number of years ago I noticed a pit from what I believe was a Hass avocado had sprouted in my garden. I let it grow for fun to see what it would do. Last year after probably 5-7 years and 20’ feet of height it bloomed for the very first time. I was so thrilled, but I started noticing small red orbs about 2-3 mm on the ground. I never got any fruit that set on the tree. I just noticed my tree is getting ready to flower again and I’m hoping some fruit might set this year.
I’ve googled small red avocado dropped fruit, but found no details.
Have you ever experienced this?
Hi Perry,
I have experienced this. Some avocado varieties have red or partly red fruitlets. They later turn green as they grow. I just checked some photos from years past and quickly found red Pinkerton and Edranol fruitlets.
The drop is a separate issue, of course. Hopefully, your tree was just still feeling juvenile last year and this year it will set some fruit. I wish you luck. Let me know how the spring unfolds.
My avocado ( unknown variety) has dropped a major part of it’s crop when they are about half grown. They fall off the stem, leaving a hollow in the top where the stem was, and go bad from there. Others talking about fruit drop seem to lose them at a younger stage with the stem still intact when they fall. Anyone know what might be causing this?
Very intetested in your article on avocado drop..
I am in Miami Fla and i have a small yard with 2 mango trees and 1 avocado tree .These 3 trees are olwer than 30 hears for sure..and 4 years ago we pfuned the avocado tree. For the first time now it is producing fruits again and drop tiny fruits like crazy..I am not sure about the type of avocado it might be Pinkerton..anyway I can send you a pic and you tell what is ??
Hi Michel,
Because you are in Florida, it would be better if you posted a picture of your tree on Tropical Fruit Forum. There are many Florida growers there who are more likely to know your variety (unless it’s a seedling).
Hi Greg,
Where can I find your watering guide? A have a 28 yr old Hass that is dropping lemon size, at about 10 a day. Not sure if I am under or over watering. We are in La Mirada/ southeast LA county. Be in the 90s pretty much since early July.
I AM iN south Africa. . i have one feuerte tree. It bare for more than 30 years. But this year, i had a big loss. About 250 avo, falling from the tree. And is beautiful big avos. I pick every week, and had conections to sell 8t to them. For extra money. But then I get stuck, of nondelivery, because they are beautiful outside, but black inside. And it look like on the end something was give it a black dot , like it was sting. What can I do. My avos are really tasteful, and I make little money.