Hass avocados are rich, creamy, pebble-skinned fruits that account for three-quarters of the world’s avocado consumption. They might seem exclusive to grocery store aisles, but you can easily grow your own Hass avocado tree with the right conditions and a little elbow grease. Learn all about avocado trees, how Hass avocados differ from other varieties, and how to plant and care for your own tree in our guide below.
History of Hass Avocado Trees
Rudolph Hass, a California mail carrier and amateur horticulturist, purchased what he believed to be Fuerte avocado seedlings in the 1920s. These were especially popular at the time. One of these seedlings grew into a tree that produced fruit unlike any other avocado known at the time, though.
Hass’s first instinct was to chop down the tree, but his children enjoyed the unique, flavorful fruit and convinced him to keep it. Hass consequently patented the tree in 1935, and every Hass avocado tree that has grown since is a product of the original tree, which lived until 2002.
The Hass avocado quickly became popular because of its creamy texture and long shelf life, and it has surpassed the Fuerte avocado as the most widely cultivated avocado across the world.
Appearance of Hass Avocado Trees
Hass avocado trees are dense evergreens that feature glossy, leathery leaves with veined patterns. These trees can grow to be 7 feet tall in a container and up to 30 feet tall if you plant them in the ground. Hass avocados have green skin while they’re on the tree, but the skin turns nubbly and dark purple-black once they’re harvested. The fruits are heavy, and usually weight between 8 and 10 ounces.
Hass Avocado Tree Specifications
- Appearance: Hass avocados feature veined, glossy leaves, and fruit that features nubbly skin that turns black once you pick it.
- Hardiness Zones: Hass avocado trees grows best in Zones 9 to 11 outdoors, and Zones 4 to 11 indoors and in a container.
- Height: The trees grow to be 7 feet tall in a container, up to 30 feet tall if you plant them in the ground.
- Lifespan: The trees can live for 200–400 years.
- Soil composition: Plant the trees in loose, sandy, or loamy, soil that drains well and has a pH of 6.5 or lower.
- Sunlight requirements: They should get a minimum of 6 hours of sunlight a day.
- Type of tree: Evergreen
Hardiness Zones for Hass Avocado Trees
USDA Hardiness Zones identify the regions in which certain plant types thrive. There are 11 Zones in total across the United States, and Hass avocado trees thrive outdoors in Zones 9-11. They prefer the warm climates of Southern California and those from the Gulf Coast through Florida.
Hass avocado trees cannot tolerate extremely cold temperatures. If you are in Zone 9, which can get cold, be sure to plant your Hass avocado tree so that it gets Southwest exposure. A Hass avocado tree that you plant in a pot indoors can live in nearly any climate in the contiguous 48 states as long as it has adequate warmth and sunlight.
Microclimates in your yard can make a real difference for cold-sensitive trees like Hass avocados. As Jenn Nawada explains on Ask This Old House, “especially if there’s a little microclimate in someone’s yard, you have a south-facing house, and you know the wind’s not gonna rip through. It’s gonna be more protected.” Planting your avocado near a south-facing wall or in a sheltered corner can bump your effective growing conditions up by half a zone or more.
Pro Tip
- Jenn Nawada, Ask This Old House landscape contractor, notes that hardiness zones are shifting over time: “It used to be just Zone 5 plants, right? Because Boston was Zone 5a and b, and then it’s kind of changed over time to 6a and b. And now it’s 7 on the coast.” If you’re on the edge of Zone 9, keep an eye on updated USDA maps — your area may be warming enough to support avocados more reliably than in past decades.
Planting Hass Avocado Trees
Buy your Hass avocado seedling from a gardening center if you decide to plant a tree. You can germinate a pit from a store-bought avocado, but it won’t bear fruit for many years, if ever.
The best time to plant your Hass avocado tree is between March and June, when soil is warm. Choose an area that has excellent drainage, sunlight, and isn’t vulnerable to too much wind.
- Root Prep: Before placing your seedling in the hole, take a moment to gently tease the roots outward from the root ball. As demonstrated in Ask This Old House planting segments, loosening the roots signals them to grow outward into their new soil rather than continuing to circle the root ball. As one TOH landscaping expert put it: “Let’s loosen up those roots so they’ll know to grow into their new home.”
Follow the steps below to plant your Hass avocado tree:
- Remove any turfgrass, weeds, or debris within 10 feet of your planting site.
- Dig a hole that’s about 3 times the diameter of the seedling’s container, and 3-4 times as deep. Hass avocado trees have shallow roots, so don’t plant your tree too deep.
- Take the seedling out of its container and place it gently into the hole. YThe root ball should be slightly above the level of the surrounding soil.
- Backfill the hole, and tamp down the soil gently.
Water your new Hass avocado tree every other day or every three days for the first week or so, and then twice weekly for the next few months. Don’t add fertilizer or compost, which can prevent the tree from acclimating to the soil.
- Watering Technique: For the deepest saturation at planting time, try the method used on Ask This Old House: plunge the hose all the way to the bottom of the hole and water from the bottom up. This ensures moisture reaches the deepest roots first and eliminates dry pockets in the backfill. Build a ring of soil around the tree’s drip line to act as a dam that holds water right where the roots need it most.
Harvesting Hass Avocados
You must harvest Hass avocados correctly to get the best flavor. Consider the tips below.
When To Harvest
Keep the variables below in mind when you’re considering harvesting your Hass avocados.
- Fruits are usually ready for harvest 6-8 months after they flower.
- Gently squeeze the fruit. It should yield slightly to pressure when it’s ripe.
- Hass avocado trees start to bear fruit after about 5 years.
- Look for a slight color change from green to purplish-black.
How To Pick and Store
Follow the steps below to harvest and store your Hass avocados.
- Allow hard avocados to ripen at room temperature for up to 5 days.
- Cut the fruit from the tree with pruning shears. Leave a short stem attached.
- Freeze ripe avocado flesh in airtight containers so that you can store it longer.
- Handle avocados carefully to avoid bruising.
- Store ripe avocados in the refrigerator for up to a week.
Common Challenges in Growing Hass Avocado Trees
Growing Hass avocado trees can be tricky. Address potential challenges by following the steps below.
Cold Sensitivity
Avocados are especially sensitive to cold, which can make growth challenging. Temperatures below 28 degrees Fahrenheit can damage or kill trees. Move container-grown trees indoors during cold spells, and use frost cloths or heat lamps to protect your avocados if you live along border climates.
Pollination Issues
Hass avocado trees are self-pollinating, but they can face the pollination challenges. Read how to address potential issues below.
- Avoid leaving your avocados in cool temperatures, which can interfere with the pollination process.
- Encourage pollinators by planting bee-friendly flowers nearby.
- Plant two trees of different flowering types (A and B) to improve fruit set.
Hass Avocado Tree Risks
Hass avocado trees are susceptible to various diseases and pests. Read more below.
Diseases
Phytophthora, which causes root rot, fruit rot, and collar rot, spreads through watering. Make sure your soil drains well and keep your tree dry to prevent this. Once phytophthora sets in, there is no way to save an established tree.
Avocado black streak causes cankers, and its cause is unknown. Proper irrigation can help you avoid this issue.
Pests
Common pests that disturb Hass avocado trees include avocado mites, avocado brown mites, and persea mites. You can treat all of these with neem oil. You can prevent mealybugs and avocado thrips by introducing ladybugs to the avocado’s environment.
Pro Tip
- Treating Mealybugs: If you spot mealybugs on your Hass avocado tree, targeted removal can be effective. As TOH’s Jenn demonstrated on the show, mealybugs are “like a white cottony bug” that “pierce the plant and they suck out the sap, and then they create this substance called honeydew.” For smaller infestations, take rubbing alcohol with a cotton pad and physically pull them off — though Jenn advises to “do a test spot on the backside” of a leaf first to make sure the alcohol won’t damage the foliage.
Caring for Your Hass Avocado Tree
Learn how to care for your Hass avocado tree correctly to keep it healthy and fruitful. Read more below.
Pruning and Maintenance
Follow the steps below to prune and maintain your Hass avocado tree:
- Prune in late winter or early spring before new growth begins.
- Remove dead, damaged, or crossing branches.
- Thin out dense areas to improve air circulation.
- Maintain a central leader so that the tree remains strong.
- Mulch around the base of the tree to retain moisture and suppress weeds.
Pruning Technique: When thinning branches, use a two-step approach to avoid damaging the tree. The first cut shortens the branch to a stub, preventing bark from ripping. The second cut removes the remaining limb just above the branch collar—the thickened area of bark where the limb emerges. This technique opens the tree’s interior to light and air, which is crucial for the formation of fruiting spurs, the twiglets that blossom and ultimately bear fruit.
Quick Tip
- Roger, TOH’s landscape contractor, advises never removing more than a third of the tree’s growth in a single season: “We’ve taken away about a third of the tree and that’s all I want to take this year. If you keep this pruning up for the next two years, then you’ll have a tree that looks like the ones we saw earlier.” When using bypass hand pruners, keep the blade oriented toward the living part of the tree so it leaves a clean cut behind—clean cuts heal faster than ragged ones.
Hass Avocados vs. Other Varieties
Read about how Hass avocados compare to other avocado types below.
Flavor and Texture Comparison
Hass avocados are different from other avocado varieties in the following ways:
- They have a creamier texture that’s best for guacamole and spreads.
- They have higher oil content, which contributes to a buttery mouthfeel.
- They have richer, nuttier flavors compared to green-skinned varieties.
- They have smaller seeds and more flesh compared to some larger varieties.
Nutritional Differences
Hass avocados feature the nutritional benefits below.
- Excellent source of fiber and antioxidants
- Higher fat content, primarily heart-healthy monounsaturated fats
- Rich in vitamins K, C, and B6, folate, and potassium
FAQ About Hass Avocado Trees
How big does a Hass avocado tree get?
Hass avocado trees can grow up to 30 feet tall in the ground and 7 feet tall in a container.
How long does it take for a Hass avocado tree to bear fruit?
It takes Hass avocado trees about five years to bear fruit.
Are Hass avocado trees self-pollinating?
Hass avocado trees can self-pollinate, as they have the parts for both male and female genders.
What is the difference between a Hass avocado and a regular avocado?
A regular green avocado may be a Florida avocado, which is lower in calories and has less fat than a Hass avocado.