The most popular avocado of all: the Hass

Nature is magical. And when it lives in a symbiotic relationship with people, it's not only powerful but also generous. The story of the Hass avocado has a lot to do with that relationship... It was an American mailman who, back in the 1920s, created the Hass variety which, to this day, is the most traded avocado in the world.

In this article we'll tell you how the Hass variety was born and look at some of its characteristics. We should say up front that here at Campos del Abuelo we've been avocado fans for quite a while.

Not only do we grow our own so you can buy the best Hass avocados you'll ever taste, we're also part of their whole journey from budding to harvest.

We consider this variety one of our gems. What makes the difference is that we don't harvest our avocados until they reach just the right oil content.

We'll explain this in more detail further down. Eduardo, farmer and founder of Campos del Abuelo, and Javier, our fellow avocado farmer, will join us to find out why, among so many avocado varieties, Hass is so popular.

But now let's head straight to California, USA, to learn the story of Rudolph Hass and his avocado tree…

The story of the mailman who gave life to the Hass avocado

Rudolph Hass settled in Pasadena with his wife and young daughter. They traveled from Milwaukee to the outskirts of Los Angeles, USA, looking for a better life.

What they didn't know was that they were settling on the land where an avocado would change their lives. Rudolph had several jobs until he landed a steady one: mailman.

One day, going about his usual route, he came across a magazine cover that really caught his eye: avocado trees where, instead of fruit, there were bags with dollar signs hanging from the branches. The picture looked something like this, but of course with money bags instead of fruit:

So the mailman felt the call and pulled some strings to be able to buy a plot of land of almost 8000 square meters, which already had avocado trees on it.

Determined to keep planting avocado trees, he bought seeds of the Lyon and Fuerte varieties and sowed them in boxes. Once he had small trees, he transplanted them into the ground.

Until the roots of baby avocado trees get a firm grip on the soil, they need a lot of attention and a lot of water too. Caring for an avocado plant isn't easy. But Rudolph had been looking after his avocado trees since they were seeds, and they took hold. In these pictures you can see the size of an avocado tree freshly planted in the ground.

The next step was grafting these new varieties onto the avocado trees already growing on the land he'd bought. But he just couldn't do it; it was as if the trees refused to accept the grafts.

Let's take a quick detour. Avocado trees, like orange trees, need to be grafted to bear fruit. We farmers have trees we call rootstocks that need to be grafted with an avocado variety to give good fruit.

It's not as simple as planting a tree or a plant. You usually don't notice, but when you buy a young tree or plant to grow fruit, the graft is already done.

That graft is what later makes the fruit you grow the variety you want. What Rudolph Hass was trying to do was graft the Lyon and Fuerte varieties onto an avocado tree.

There are several ways to graft, for example by making a T-shaped cut in the bark of the rootstock. Then you look for a strong shoot from a tree of the variety you want, cut a small piece of it and insert it into the T-cut you made in the rootstock.

In these pictures you can see how a side graft is done.

Back to our story. Hass's problem was that grafting can only be done in spring. And the third time the tree grafted by Rudolph failed to bear fruit, he wanted to give up and even pull the tree out. Luckily, he didn't…

The following year, that same plant gave 3 avocados, and the year after, 125. At first Hass thought they were odd: too dark, with bumpy skin; he even said they looked rotten. But when he tasted them with his family, they discovered the flavor and creaminess of the fruit were incredible.

Mr. Hass started selling them retail, until a colleague who knew the business encouraged him to send a box of avocados to Chicago and back. To everyone's delight, they came back in perfect condition.

And so, in 1935 Rudolph patented the mother tree under his own surname: Hass. The funny thing is that, even though he got into avocados because of that picture of a tree full of money bags, Hass never got rich. He retired as a mailman and, although he made some money from avocados, it was never his main income.

Every Hass avocado comes from the tree Rudolph grafted. Until 2002 you could visit this tree, but then it got sick and had to be cut down. The legacy of the mailman and his tree lives on all over the world: wherever a Hass avocado goes, this story goes with it.

The Hass variety doesn't just have a fascinating story; it also has a set of features that make it the most popular avocado internationally and the most widely grown in the world…

Hass avocado characteristics, with our farmers

The Hass avocado tree is a vigorous grower, with horizontal branches forming a sort of inverted crown with a semi-open shape. One advantage of this tree is its resistance to temperature swings. Though there are a few things to keep in mind, which our farmers will explain.

When the fruit sets and ripens, it hangs from the tree in clusters. Though of course, the best moment is when they're ready for a tasty guacamole... In these pictures you can see the avocado trees: they're the first three in the row. You can also see the fruit when it's almost ready to be picked, and an avocado ready to eat.

When it comes to the best temperature for growing avocados, keep in mind that frost will slow their growth or can even kill the tree.

On the subject of temperature, Eduardo, avocado farmer, tells us:

If the temperature drops to 1º, we lose the tree. But it depends on other things too; for example, if the tree has plenty of moisture, it handles the cold better.

Often it's worse to have -1º for an hour than -5º for about 10 minutes. Another thing is that if there's wind, the tree holds up better because the cold doesn't settle on it.

That's why it's important to grow it in warm areas, places where it doesn't freeze. And if there's frost (that ice that forms in the mornings, frozen dew), the crop is lost too.

You have to be very careful with temperature. Another thing that can affect the avocado tree is the hot westerly wind, the poniente… That's not good either, because it dries the tree out and makes it drop its leaves.

Hass avocado trees are very generous trees and start producing 2 or 3 years after planting (exactly how long Rudolph the mailman had to wait to see his first avocados).

According to Eduardo, at full production they yield roughly 1000 kg per hanegada (a traditional Valencian land measure), which works out to about 10,000 to 12,000 kg per hectare.

They flower in spring, between March and April. As farmers, we see it as a real advantage that the fruit can stay on the tree a long time without spoiling, so when picking time comes there's no need to harvest them all at once.

That's why one of its traits is a long harvest. For this variety, the harvest runs from December to May.

Avocados have a type of pollination called “cross-pollination”. This means that, for pollination to happen, you need two different types of avocado.

Hass, for example, is a type A, so it needs type B pollinators, like the Bacon avocado variety. If you'd like to know more about avocado cross-pollination, we invite you to read our article on the history and growing of avocados.

Anyway, Eduardo told us from his avocado grove that the best are always the natural pollinators: our beloved bees. He explains: you have to put in beehives. Pollinator trees are usually planted because the wind carries the pollen, but it's more effective to let the bees do all that work themselves. Lots of people don't plant pollinators anymore for this very reason.

What is the fruit of the Hass avocado tree like?

The fruit is green, but when it ripens and is ready to eat, its skin turns dark purple, almost black. The skin is tough, thick and a bit rough. Its flesh is yellowish, with a flavor that reminds us of nuts like walnuts or hazelnuts.

The fruit is smaller than others. In fact, its seed is smaller too, so relative to the whole fruit, there's more flesh to enjoy. A Hass avocado usually weighs between 200 and 350 grams. Another feature is that, unlike other varieties, it isn't stringy.

As we saw at the start, in the story of the Hass avocado's creator, its thick, bumpy skin makes it very resistant to shipping. That's another reason it's the avocado that travels the most around the world.

Since we had the chance to ask two avocado farmers about growing them, we asked them both the same question: why is Hass the most popular variety?

Javier answered like this: it's the most popular not only for its flavor, but for its tough, bumpy skin that protects it during export. Unlike, say, the Bacon avocado, which has thinner skin, this one is the king of exports thanks to that protective layer.

And besides being exportable without getting damaged, to this day there are practically no pests, the tree yields well and the fruit tastes magnificent. That's why it's the most traded…

Eduardo, for his part, pointed out: the selling season lasts a long time, it has a big production volume, and the fruit size is good too… Look, shoppers don't want huge avocados only to leave half in the fridge.

And last but not least, they're amazing to eat, with that lovely nutty flavor and just the right amount of oil. Hass avocados also ripen easily.

Picking up on Eduardo's words: if you're not sure how to store a cut avocado, here's a simple guide. And if you want to know when an avocado is ready to eat, we recommend this short article from our blog.

When is the right moment to harvest Hass avocados?

Avocados don't ripen on the tree, and they should be harvested once they've reached the right oil content. Once picked, they finish ripening off the tree.

Sadly, they're often picked before reaching the right oil content. The problem is that avocados harvested too early will never reach their best or ripen properly.

Javier, out in the field, puts it perfectly: the avocado is a climacteric fruit, which means it doesn't ripen on the tree; it finishes ripening (that is, it gets softer) once it's picked. The most important thing is to pick it when the avocado has the right oil content.

You don't pick it earlier simply because the oil isn't properly developed; if you pick it too soon, it won't finish ripening off the tree. That's what happens in many countries: it's picked for export, it may arrive here hard and never ripen... and worst of all, when it does ripen, it turns black.

At Campos del Abuelo we respect nature's cycles, and that's why our avocados are harvested at exactly the right oil content, so to enjoy them at their best they need to go through the ripening process. In this article we explain how to ripen your avocados naturally.

And just in case, here's a video where Eduardo, a seasoned farmer, gives you a very wise tip about avocados and ripening, because, as he says, you have to be patient:

Just like the Hass avocado has its story, so do other varieties. The Bacon variety that came from California, the Fuerte avocado, Pinkerton or Lamb Hass were born from crosses between races and varieties and are usually named after their creators. Chances are not all of them star a mailman, but they're sure to be just as interesting.

For now, from Campos del Abuelo, it warms our hearts to know we're part of the story of one of our gems: the Hass avocado.

Remember, in our online shop you can buy Hass avocados and fruit and vegetables straight from the farmer, with no post-harvest chemicals.

Until the next story, and thanks for reading!