Hass avocados are the most popular avocados out there—these rich, creamy, pebble-skinned fruits account for about three-quarters of the avocados eaten worldwide. While farmers and grocery stores relish these fruits for their impressive shelf life, there’s nothing better than a home-grown Hass avocado. With the right conditions and a little work, your Hass avocado tree will bear nutritious fruit in about five years.
I. Appearance and Characteristics
The Persea americana ‘Hass’ is a renowned variety whose fruits are standard on our stalls. It can reach 7 m in open ground in our latitudes but only 2 to 3 m in height when grown in pots. The fruit is initially green, with a granular skin, then black-brown with violet reflections when ripe. It is climacteric: it only ripens after picking. Harvesting and storing it in a cool and dry space is necessary for it to ripen. The large-sized fruits have firm, stringless flesh. They weigh an average of 300 grams and contain numerous vitamins, minerals, and trace elements.
‘Hass’ is a self-fertile protogynous cultivar, capable of self-pollination, as its flowers open twice, first as female and then as male. However, it is preferable to cultivate several plants nearby to ensure pollination. It is classified as category A, and it is recommended to plant category B varieties nearby for good pollination, such as ‘Bacon’, ‘Fuerte’, or ‘Zutano’. Furthermore, fruits will only appear if the tree has sufficient sunlight and high humidity during the initial fruit formation phase.

The Fun Chronicles
CC0 1.0
The Persea americana ‘Hass’ can only be acclimated in open ground in our mildest winter regions, in warm oceanic or Mediterranean climates. It tolerates frosts of up to approximately -4°C. Elsewhere, it is cultivated in pots like a citrus tree, which allows it to be stored away from frost in winter in a bright but unheated room. A greenhouse can obtain the necessary humidity conditions for fruiting.
II. How to Grow and Care
Sunlight
For a lush, leafy canopy and bloom production, Hass avocado trees should receive at least six hours of bright, indirect sunlight. These trees can tolerate light shade, too, but too much and the tree’s foliage growth will be hindered.
Temperature and Humidity
The Hass avocado tree is mainly considered hardy in USDA growing zones 9 to 11. It does best with moderately warm and humid temperatures; between 60°F and 85°F with average-to-high humidity is considered ideal.
The tree won’t tolerate freezing temperatures so in climates that see temperatures dip below freezing, the best option is to grow the tree as a container plant that can be sheltered indoors in the winter.
Watering
Hass avocado trees require regular watering. Once per week is a good baseline for mature trees, but take into account recent rainfall or humidity levels.
The top inch or so of soil should be dry before watering again. Water to restore soil moisture but don’t allow the soil to become drenched and soggy.
Soil
The soil for growing a Hass avocado tree should be loose and well-draining. Loamy or sandy soil will support healthy root growth but heavy clay soil should be avoided because of poor drainage.

The Fun Chronicles
CC0 1.0
Fertilizing
Hass avocado trees are heavy feeders. Plan on fertilizing trees during the spring, summer, and fall with a well-balanced NPK formula applied to the soil.
In addition, apply a foliar fertilizer to the leaves in the spring. Zinc and nitrogen should be applied to the soil in spring, summer, and fall, plus a foliar fertilizer application of zinc in the spring.
Planting Instructions
When you decide to plant your Hass avocado tree, make sure to buy your seedling from a gardening center. While you can germinate a pit from a store-bought avocado, it won’t bear fruit for many years, if at all.
Here are the steps to take when planting your Hass avocado tree:
- Remove any turfgrass, weeds, or debris within a 10-foot diameter of where you want to plant your new seedling.
- Dig a hole about three times the diameter of the seedling’s container and 3–4 times as deep. It’s important that you don’t plant your tree too deep, as avocado trees have shallow roots.
- Take the seedling out of its container and place it gently into the hole. You want the root ball to be slightly above the level of the surrounding soil.
- Backfill the hole and tamp down the soil gently.
You’ll need to water your newly-planted 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. Adding fertilizer or compost is not advisable, because you want your tree to acclimate to the soil as soon as it can.
Pruning

阿橋花譜 KHQ Flower Guide
CC BY-SA 2.0
In general, avocado trees don’t require much pruning and Hass avocado trees aren’t any different. You should avoid over- or under-pruning the tree.
To do that, prune to remove dead wood and maintain a conical shape that allows easy access to the tree’s branches and sufficient light penetration and airflow.
Propagation
As a cultivar, a Hass avocado tree can only be propagated through grafting and it’s best done in the spring. If you have the skills and tools to graft a tree—including a healthy rootstock specimen—here’s how to do it:
- Gather the following supplies: sharp snips, a sharp knife, and something to cover the grafted area, such as grafting tape.
- Select a section of new growth between 5 and 6 inches long with several unopened leaf buds.
- Using the snips, cut the new growth branch at a 45-degree angle.
- Remove the tip of the cutting, along with any leaves that are present.
- On the tree you’ll be grafting onto, wound the tree by removing a section of the bark.
- Take the cutting and position it onto the grafting site, with the cambium of the cutting and the cambium of the grafted tree making contact.
- Use grafting tape to secure the cutting to the graft tree, covering all exposed areas.
- After several weeks, the grafted branch and the main tree should be fused together.
Potting and Repotting
Like other types of avocado trees, you can grow a Hass avocado tree in a pot and this is especially recommended if you live in USDA hardiness zones 8 or below.
In zone 8, you may be able to overwinter the tree outdoors. Beyond that, you’ll need to grow the avocado tree indoors or be prepared to move it inside during cold weather months.
Hass avocado trees grown indoors usually mature to a height of 5 to 7 feet. For store-bought trees that are already several feet tall, you should choose a large container. Pick a pot with drainage holes to prevent the soil from becoming waterlogged, which can lead to root rot. Fill the container with a loose soil mix; cactus or succulent soil mix works well. Plant the tree—covering the root ball—and water thoroughly.
Depending on how large of a container you choose, you may not need to replant the tree for several years.
Overwintering

The Fun Chronicles
CC0 1.0
Hass avocado trees grown in USDA zones 9 to 11 will require no special accommodations since the year-round temperatures remain well above freezing.
If you plan to grow this type of tree in USDA zone 8, you’ll need to provide the tree with some additional protection during the colder months of the year. If temperatures are forecasted to drop below freezing, cover the base of the tree with a frost blanket.
It’s also helpful if the tree has been planted beneath an overhang or with a south-facing orientation in the shelter of a nearby building. If your Hass avocado tree is grown in a container, you can move it to a protected location when cold weather is imminent.
Pests and Diseases
Common Pests
Many different mites can attack your hass avocado trees. The most common are the avocado mite, the persea mite, and the avocado brown mite. All of these respond well to treatment with neem oil.
A particular kind of thrips, avocado thrips are a relatively new pest that California growers are battling. At this time, the University of California recommends using environmental controls like beneficial insects to get rid of them. They generally cause cosmetic damage to your avocados rather than permanent tree damage.
Mealybugs and ants are an evil pairing for avocado growers. Getting rid of both simultaneously is wise. A wide band of sticky material around the trunk can prevent ants from climbing the tree. Ladybugs will then handle your mealybugs while they’re keeping your plant thrips-free.
Three different forms of avocado worm exist. These are all forms of leafrollers, and they go after your produce as well as the leaves. Bacillus thurigiensis is effective against them without causing damage to your beneficial insects.
Common Diseases

The Fun Chronicles
CC0 1.0
The most damaging fungus to avocado trees is phytophthora. This in various forms can cause root rot, collar rot (a form of canker on the trunk) and fruit rot. In all cases, this spreads via watering. Keep trees and leaves dry. Ensure your soil drains extremely well without becoming muddy. Prevention is essential as there are no cures for phytophthora once established in your tree.
Avocado black streak is a canker-causing pathogen, but its cause is unknown. This creates black lesions on the trunk or branches which can crack and ooze sap. It appears most often after drought stress or exposure to excess salts, and can be fatal to the tree. Practice good irrigation with high-quality water.
Dothiorella canker is also common in Hass avocado trees. These cankers are not black, but they also crack. The sap they exude dries into a white powder. Carefully scraping off the outer bark on the canker to remove it can help portions to heal. It can cause the tree to look sickly, but the trunk generally continues to survive.
III. Uses and Benefits
The Hass Avocado is the most popular avocado in America – known for its creamy, delicious texture used in guacamole, salads, and tacos.