Hass avocado

The Hass avocado is a large fruit, typically weighing between 200 and 300 grams, with a dark green, bumpy exterior. As it ripens, its skin shifts to a deep purplish-black and softens under gentle pressure. Inside, the flesh is pale green near the skin, transitioning to a richer yellow-green toward the center.

This variety was first cultivated and sold by Rudolph Hass, a Southern California mail carrier and amateur horticulturist, who lent it his name. Thanks to its long shelf life, high yield, and year-round harvest potential in some regions, the Hass has become the world’s most popular avocado. In the United States, it makes up over 80% of the avocado crop and 95% of California’s output, and it is also the leading avocado variety grown in New Zealand.

History

Every commercial Hass avocado tree originates from grafted seedlings of a single parent tree. That tree grew from a seed purchased by Rudolph Hass in 1926 from A. R. Rideout of Whittier, California, who sourced seeds from any available place, including restaurant scraps. The seed’s original cultivar remains unknown. A 2019 genetic study published by the National Academy of Sciences revealed that the Hass avocado is a hybrid, with 61% Mexican and 39% Guatemalan ancestry.

In 1926, Hass planted three seeds from Rideout on his 1.5-acre grove at 430 West Road in La Habra Heights, California. Only one seedling thrived. After two failed attempts to graft it with branches from the popular Fuerte avocado, Hass considered cutting it down, but a professional grafter named Caulkins assured him the tree was healthy.

When it began producing unusual, bumpy fruit, Hass’s children enjoyed the taste. As yields increased, he sold the surplus to coworkers at the post office. The Hass avocado gained early commercial success at the Model Grocery Store on Colorado Street in Pasadena, where chefs for wealthy residents paid $1 each—a steep price at the time—for the large, nutty fruit.

Hass patented the tree in 1935 and partnered with Whittier nurseryman Harold Brokaw to grow and sell grafted seedlings from its cuttings, with Brokaw receiving 75% of the profits. Brokaw specialized in the Hass, often selling out of seedlings because, unlike the Fuerte, Hass trees produce year-round, with larger fruit, a longer shelf life, and a richer flavor due to higher oil content. By the early 21st century, the U.S. avocado industry earned over $1 billion annually from the Hass cultivar, which accounted for about 80% of all avocados grown worldwide.

The mother tree

The name “Hass” (rhyming with “pass”) is sometimes misspelled as “Haas” in U.S. supermarkets. The original mother tree stood in front of a residence in La Habra Heights for decades, succumbing to root rot at age 76 and being cut down on September 11, 2002. Its wood was stored at a nursery, awaiting a historic emblem as of 2008.

Bearing pattern

Hass avocado trees may bear fruit heavily only every other year. A low-yield season, often due to cold intolerance, can be followed by a very high yield the next year. However, a heavy crop can deplete stored carbohydrates, reducing the following season’s yield and potentially establishing a lifelong alternate bearing pattern. Southern California groves benefit from good soil, drainage, ample sunlight, and cool ocean breezes, allowing for fresh harvests year-round.

Nutritional value

A raw, peeled Hass avocado is composed of 67% water, 20% fat, 8% carbohydrates, and 2% protein. Per 100 grams, it provides 206 calories and is rich in folate and copper (over 20% of the Daily Value), with moderate amounts of vitamin B6 and potassium (15–19% DV). It also contains phytosterols and carotenoids, including lutein and zeaxanthin.