HOW TO GROW A COLD-HARDY AVOCADO TREE — OUTDOORS — IN VANCOUVER, CANADA
(Or Seattle, WA; Portland, OR; Northern California; Atlanta, GA; Raleigh, NC; or Little Rock, AR; (or even Reyjkavic, Iceland), or any other cooler zone where Avocado trees are currently viewed as “unlikely to succeed.”)
(If you haven’t read my original article, you can visit it here: The B.C. Avocado Project).
DO YOU WANT TO GROW A COLD-HARDY AVOCADO TREE IN VANCOUVER, CANADA?
THE GOOD NEWS IS, THAT IT’S ALREADY BEING DONE! An acquaintance of mine told me last week that he already has a couple of Avocado trees that have been growing in his Burnaby (British Columbia) backyard for 3 years already. He grew them by accident, after tossing a bunch of Avocado seeds into his compost 3 years ago. Some sprouted, most died. But these 2 Avocado trees have SURVIVED THREE CONSECUTIVE B.C. winters without any protection — at all — from the elements.
These 2 Avocado trees have already survived -8°C (18°F) on at least 3 occasions without any ill effects. That’s pretty good results from Avocado seeds that my friend got from the grocery store.
THE NEXT 4 PARAGRAPHS ARE THE MOST BASIC THINGS TO KNOW:
- It’s really simple. Even a 10-year old child could succeed at this.
2. Just plant a lot of Avocado seeds. Many will sprout. Most will die in their first Winter. But 2% to 10% of them will be cold-hardy enough to survive the Vancouver, BC winter.
3. It’s just a “numbers game.” Each seed is genetically different from all other Avocado seeds. Some are wired to be more cold-tolerant than others. So if you plant many seeds, you’ll get a few that will naturally survive the cold weather that we have around here (There are some Avocado trees that can routinely survive a winter low of -10°C and still produce a crop of fruit the following Summer).
4. You’re already eating enough Avocados each year to get your own Cold-hardy Avocado tree… Stop wasting your seeds — PLANT THEM!
NOW THAT YOU HAVE THE BASICS, YOU CAN NOW SLOWLY ABSORB THE REST OF THE DETAILS:
If you don’t have any experience growing Avocado seeds, or if you’ve had a bad experience), just watch a couple of YouTube.com videos on the subject and copy-cat what they do. Or you can just plant them in the compost outside like my Burnaby friend did.
Either way, you’ll achieve some success.
I will show you in this article, the steps that you can take to get your own Cold-Hardy Avocado tree started this year.
STEP 1: Collect at least 10–15 Avocado seeds. Just get them from whatever Avocados that you buy from the store. Or any Avocado seed that someone gives to you.
One word of advice: If the Avocado variety that you have is one that originated in Guatemala, it likely will not do well. The most cold-hardy Avocado varieties all originated from Mexico.
Fortunately, most Avocado varieties sold in North America are descendants of Mexican varieties: Hass (61% Mexican), Fuerte, Reed, Bacon, and many others. Hass Avocados account for over 70% of the world’s commercial Avocado production.
STEP 2: Start your seed in the usual glass of water (and then transfer it into a pot), or just plant it directly into a pot with soil in it. Either way works. But be patient. Avocado seeds take 1 to 2 months just to sprout. Sometimes longer.
There are various methods for growing Avocado seeds. I recommend viewing a few videos like the 2 below. They could save you a month or more of waiting for your seedling to sprout and grow (I had one seed that took 4 months to sprout!). If you do it right, you can often get the sprouting started in 1 to 3 weeks. See these videos for more information (and there are other good videos online):
STEP 3: Grow them indoors for one to several months, until they are ready to be transplanted outdoors. As soon as it reaches the March 21 to July 15th window of time, I transplant as many Baby Avocado trees outside as I can. After that, they’re on their own!
STEP 4: Plant several seedlings, if you can (I recommend planting at least 10 seedlings). Remember: for every 20 Avocado seedlings that you plant, you’ll end up with only 1 or 2 cold-hardy Avocado trees next spring. Mother Nature may be harsh, but how else can you identify the cold-hardy ones?
If we have an unusually cold winter, maybe they’ll all die. But if that happens, just start over again next year. Once you get one or more trees established, they will grow up again from the roots in the Spring if the top (the part above the ground) ever dies off during a hard freeze.
STEP 5: When you transplant the baby Avocado trees outdoors, plant them about 1/3 meter (1 foot) apart. Don’t worry that they’ll be crowded. Mother Nature will solve that issue come winter time. 90% of your baby trees will freeze to death.
Think big. Avocado trees can get pretty large, so don’t plant one right next to the foundation of your house. Put it at least 6 feet away from your foundation.
Also, never plant an Avocado tree where water likes to collect (ie. near puddles). Overwatering or flooding are the death knell to Avocado trees. Good drainage is essential.
STEP 6: Plant the seedlings into regular soil, without any enhancements (ie. don’t put lots of organic matter into the soil when you bury the roots). You are more likely to get root rot in your Avocado tree if you have lots of organic material underground, according to one expert.
STEP 7: However, on top of the soil (around the base of the tree), I have placed a layer of wood chips (about 6–8 inches thick), as insulation, in order to protect the roots from the winter cold. That way, the roots won’t be killed off by the winter cold if we should have an extreme cold spell that kills off the top (above-ground) part of the tree.
STEP 8: Wait 3 to 5 years before any of your trees begin bearing fruit. Some Avocado trees will produce fruit after only 3-4 years. Others may not fruit for up to 10–12 years. You will likely improve your chances of getting early fruit by planting multiple trees.
POSSIBLE QUESTIONS:
Q. What happens when we have a colder-than-normal Winter?
A. More of your trees will die. That is one reason why it’s important to grow multiple Avocado trees. Even though a frost-killed tree will often grow back from the roots the following Spring, it is even better if we can obtain varieties that will withstand even colder temperatures during an exceptionally cold winter.
Over time, our varieties will be even more cold-resistant than our initial varieties, because we will be specifically breeding and growing with that particular trait in mind.
Q. Why are Mexican Avocado varieties more cold-resistant?
A. This is because Avocados originally started in Mexico. And there are some areas in Mexico, way up in the mountains, where Avocado trees grow and proliferate, where it regularly freezes during the winter. Avocado trees from these areas already contain the DNA that allows these trees to survive sub-freezing weather. Some of this cold-hardy DNA is present in many of the popular commercial varieties.
One Mexican friend that I spoke with (who is from the area where the cold-hardy varieties grow in the mountains) told me that the Avocados that come from that area, all have VERY LARGE seeds. This may be a significant observation. What this implies, is that if we are able to obtain some Avocados from this mountainous area, we could then plant these larger seeds and possibly get even more of that cold-hardiness trait that we need for our Vancouver, B.C. Avocado Project.
Of course, if the super cold-hardy Avocado varieties of the future contain larger-than-average seeds, I won’t complain any. It’s better than not being able to grow any Avocados at all in Vancouver.
If any of you has a way to legally import some of these large-seed Avocados from the cooler mountainous region of Mexico, please do so. And then plant the seeds, so that we can improve our future cold-hardy Avocado varieties.
Q. Do you have any back up system, in case no acceptable Avocado varieties come from this project, anytime soon?
A. Yes. I have 3 different Avocado trees that I grow indoors during the Winter. Each is planted in a large plastic garbage can filled with soil, or in a large laundry basket. I wheel them outside during the Spring, and wheel them back indoors during the next Winter. That way, I’ll enjoy at least a few home-grown Avocados until we can come up with a true cold-hardy variety that is adequate for the Vancouver climate. These 3 trees were also grown from seed just like the others that I have planted outdoors. But you can certainly grow a “name brand” variety indoors, if it won’t be going outside anyway (ie. Hass, Fuerte, Reed, Bacon, etc.).
Q. When Avocado trees get blossoms, what can I do to enhance pollination?
A. There are two things that you can do: 1. You can hand-pollinate with a small paint brush, and/or 2. You can mix a little bit of honey with some water, and spray it lightly on the Avocado blossoms to attract the bees (this really works). There are separate web articles and YouTube videos on each of these methods.
Q. I’ve planted Avocado seeds several times and they always do well for a few weeks, then they die.
A. The commonest complaint that I hear is this one. The commonest reason why people kill their Avocado tree is that they OVER-WATER it. Avocado trees get root rot pretty easily. Once you take the seed out of the glass-filled-with-water, then you don’t want to overwater your tree any more. Just water it once or twice per week if it’s in a pot. Not more than twice per week, unless it’s pretty hot.
After you plant an Avocado tree outside in Vancouver, you don’t need to water it much. This is a rainy city. But if we go a long while with no rain, it’s OK to water your Avocado tree.
Q. How do I protect my Avocado tree from sunburn?
A. Very easy. For the first few years in the life of an Avocado tree, it helps to grow the tree in partial shade. The ideal is to grow the Avocado tree in the shade of another tree that you plan on cutting down in 3 or 4 years.
If the Avocado tree is always in full sun, the tree will get sunburned on the exposed trunk and branches. This will expose the tree to more pests and diseases, and could kill the tree.
If you can’t avoid putting the tree in full sun, then you can also do this: mix about 1 cup of white, indoor latex paint, with one cup of water. After mixing the paint and water into a 50–50 solution, paint the trunk and exposed branches with this thinned-down “whitewash” paint. This “whitewash” mix will protect your Avocado tree from sunburn.
Q. About 90% of all Avocados sold in the USA and Canada are Hass Avocados. I’ve read that Hass Avocados are a Guatemalan variety, so I’m wasting my time if I think I’ll get a cold-hardy tree from a Hass Avocado seed, right?
A. I have good news for you: Recently, scientists have sequenced the genome for the Hass Avocado. It turns out that the Hass is about 61% MEXICAN, and about 39% Guatemalan. So, if you have no other options for planting than Hass Avocado seeds, you still have a good chance of producing a few resulting seedlings that are cold-hardy. Just keep planting and growing. Sooner or later you’ll get something that will be hardy down to at least -7°C, and maybe -10°C and still produce a crop the following summer.
Q. What if I obtain a cold-hardy Avocado variety from a nursery? Wouldn’t that be just as good?
A. It could be just as good. But here in Canada I haven’t heard of any of the commercial, very-cold-hardy varieties making it here yet. The Duke and the Aravaipa Avocado varieties (mentioned in my article “The B.C. Avocado Project”) still are not available in Canada, as far as I know. Other interesting possible cold-hardy varieties are mentioned on https://floridafruitgeek.com/cold-hardy-avocados/, such as Del Rio, Wilma, May, Gloria, and several others. The three of these that I find most interesting are Del Rio (which has been known to survive -15°C (7°F) without killing the entire plant down to the ground[the last time it was colder than -15°C in Vancouver was over 50 years ago! — George]), May (which is an early-ripening variety, which would be a godsend for Vancouver, considering our short growing season), and Gloria (which is extremely short-seasoned — ripening in Mid-June [in Florida]).
All of these existing varieties should be imported, tried and tested in the Vancouver area. But until we have some of these — in hand — our best option is to keep developing our own “Canadian variety.”
The most cold-hardy Avocado tree that I’ve heard of in a Canadian nursery is good down to about -7°C (about 20°F). But in almost every Vancouver winter in the past 10 years, it has reached down to at least -8°C (18°F).
That simply isn’t good enough for Vancouver, BC. We need trees that will be good down to at least -10°C (14°F). And they do exist! If you read the article about the Avocado trees that are growing in London, England (see link below), you’ll see that all of them survived the 2012 London, UK cold snap that reached down to 10°C.
The exciting thing about all these above-mentioned cold-hardy Avocado varieties is that they PROVE, BEYOND DOUBT that the existence of a cold-hardy, short-seasoned variety of Avocado that is capable of growing well in Western Canada is truly possible. (And it may even already exist, if we can import the right trees).
One word of caution: Western British Columbia has many environmental factors, like climate, flora, pests, fungi, etc. that are different from other areas where Avocado trees are grown. We can’t say for sure whether any of the above cold-hardy varieties would be ideal for the Vancouver area, without a few years of growing and testing, outdoors, just to be sure that they really will grow well here. This is just one more reason why we still need to work on developing our own Canadian variety while we also search for other suitable cold-hardy Avocado varieties.
Q. I don’t have much space in my yard to grow 9 to 16 Avocado seedlings. How can I make the room for them?
A. Easy — plant them close together! All you need to do is to take the 1-Square-Meter-Challenge! Set aside a 1 meter x 1 meter square in your yard that’s reserved for 9 seedlings (be sure to choose a spot that doesn’t get lots of direct sunlight — Avocado seedlings don’t do well in direct sunlight until they are a few years old). Then simply transplant each seedling ½ meter apart, in a grid format, starting at one of the corners (that would make 3 rows with 3 seedlings in each row). When you’re done, you’ll have 9 baby Avocado trees growing in one square meter!
You could even try growing 16 seedlings in the same Square Meter by planting them 1/3 meter apart in the same grid format (ending up with 4 rows of 4 seedlings per row).
Don’t worry that they look crowded. Mother Nature will fix that. In the winter, most of them will die, leaving 1 or 2 cold-hardy Avocado trees remaining. Next Spring, the surviving tree(s) will have plenty of room to grow. If they all die, just do it again one more time, and you’ll likely get a survivor the second time around.
Q. What are my chances of actually getting a crop of Avocados from an Avocado tree in Vancouver, Canada.
A. Actually, the chances are very good. London, England has a climate that is virtually identical to the Vancouver, BC climate. And people are already harvesting ripe Avocados in London (see the article linked below the author’s bio).
However, there is some evidence online that a few fruit-laden Avocado trees have already been spotted in the Vancouver area. (There are two western BC areas that have been mentioned online as having Avocado trees with Avocados growing on them are: 1. The Riley Park neighborhood in Vancouver [this is located near Queen Elizabeth Park], and 2. Someone said they spotted a 50-ft tall Avocado tree, with Avocados on it, in Maple Ridge (about an hour from Vancouver) in about 2015.
(If you do spot a Vancouver-area Avocado tree with Avocados growing on it, please let me know. And please consider posting a YouTube video of it online, if you can appropriately do so. This will document your find for all the world to see.)
Q. How about a small, portable greenhouse to protect my Avocado tree outside during the winter cold spells? Is something like this a possibility in Vancouver, BC or anywhere else where it gets icy-cold in the winter?
A. Definitely, YES. There are available some economical, easily-assembled portable greenhouses that you can purchase for under $100 (USD). Here is one example:
I am not endorsing this particular company. I am simply demonstrating that this concept is available. And it’s not horribly expensive to get one ($99 USD +S&H). This company ships worldwide, so you can get it no matter where you live.
The advantage is this: Once you have a nice little greenhouse like this, you could use this to have some dedicated space for your Avocado tree in your yard or garden. And, even if we were to have a record cold Vancouver winter where it gets -20° C (-3°F) during the winter (the actual all-time record Vancouver winter cold was -17.8°C (0°F) in 1968 and in 1950), you could easily keep your Avocado tree alive if it were a good, “cold-hardy variety.”
Here’s an example of how you could achieve this:
Let’s say that on a cold winter’s night in Vancouver, it will get -20°C (-3°F). If you have a cold-hardy Avocado tree that will withstand -7°C (20°F)(ie. Stewart or Mexicola Grande varieties). You can easily set up some sort of source of gentle heat to provide some partial warmth within your tiny greenhouse that will raise the inside temperature to at least -7°C, so that the Avocado tree within it will survive the deep freeze outside. (You don’t have to raise the temperature in the greenhouse to be above freezing. You only have to raise it enough to prevent the Avocado tree from dying)
Possible sources of gentle heat: 1. Heating mats, 2. electric blanket(s), 3. Christmas lights (the old ones that give out some heat — not the new LED lights)
One advantage of planting your Avocado tree outdoors and then having a nice little greenhouse surrounding it, is that your tree would be able to grow much larger than it would if you were to keep it in the house (in a large pot). Obviously, by being in this greenhouse, your Avocado tree would now be able to grow up to about 7 feet high on one side, and would be able to produce up to 75 or even 100 fruits in a good year. This would be plenty of fruit for 1 family. And would even give you enough to share with a few friends.
Another advantage is that, by having the greenhouse around the Avocado tree, it will blossom earlier in the year than it normally would, and would therefore produce a crop earlier in the season than would otherwise be possible. For clever people who have enough space in their yard or property, they could set up 2 or 3 of these greenhouses, and plant different varieties of Avocado trees, thereby giving themselves varieties that will ripen at different times. That way, they will be able to extend the timeframe where they can go outside and pick a continuous supply of fresh Avocados in Vancouver.
This harvest season could begin as early as August with some varieties and could continue into December (or later) for other varieties.
Really, the sky’s the limit. And it’s so easy to accomplish!
What’s stopping you?
— George Stancliffe
P.S. — George Stancliffe is interested in creating a home variety of Avocado that will produce fruit in the Vancouver, Canada climate.
George Stancliffe has also written extensively on how you can teach your child to Speed Read, regardless of his/her age (Even if your child is ADHD or Dyslexic). You can find many of his articles here on Medium.com. You can also find more information on his website: www.SpeedReading4Kids.com .
If you want more information on growing Avocados in Vancouver or in other cooler areas, you may be interested in the following articles:
1. They’re Already Harvesting Large, Ripe Avocados in London, England — Why Not in Vancouver, Canada? — https://georgestancliffe.medium.com/theyre-already-harvesting-large-ripe-avocados-in-london-england-why-not-in-vancouver-canada-2819a58070e8
2. The B.C. Avocado Project — https://georgestancliffe.medium.com/the-b-c-avocado-project-670ed22a74d7