The Hass avocado is a cultivar of avocado with dark green-colored, bumpy skin. It was first grown and sold by Southern California mail carrier and amateur horticulturist Rudolph Hass, who also gave it his name.
The Hass avocado is a large-sized fruit weighing 200-300?grams. When ripe the skin becomes a dark purplish-black and yields to gentle pressure. When ready to serve, it becomes white-green in the middle part of the inner fruit.
Owing to its taste, size, shelf-life, high growing yield and in some areas, year-round harvesting, the Hass cultivar is the most commercially popular avocado worldwide. In the United States it accounts for more than 80% of the avocado crop, 95% of the California crop and is the most widely grown avocado in New Zealand.
A young Hass avocado sprout
All commercial, fruit-bearing Hass avocado trees have been grown from grafted seedlings propagated from a single tree which was grown from a seed bought by Rudolph Hass in 1926 from A. R. Rideout of Whittier, California. At the time, Rideout was getting seeds from any source he could find, even restaurant food scraps. The subspecies of this seed is not known and may already have been cross-pollinated when Hass bought it.
In 1926, at his 1.5-acre grove at 430 West Road, La Habra Heights, California, Hass planted three seeds he had bought from Rideout, which yielded one strong seedling. After trying and failing at least twice to graft the seedling with branches from Fuerte avocado trees (the leading commercial cultivar at the time), Hass thought of cutting it down but a professional grafter named Caulkins told him the young tree was sound and strong, so he let it be. When the tree began bearing odd, bumpy fruit, his children liked the taste. As the tree’s yields grew bigger, Hass easily sold what his family didn’t eat to co-workers at the post office. The Hass avocado had one of its first commercial successes at the Model Grocery Store on Colorado Street in Pasadena, California, where chefs working for some of the town’s wealthy residents bought the new cultivar’s big, nutty-tasting fruit for $1 each, a very high price at the time (more than US$15.00 of inflation adjusted value by 2007).
Hass patented the tree in 1935 (the first US patent on a tree) and made a contract with Whittier nurseryman Harold Brokaw to grow and sell grafted seedlings propagated from its cuttings with Brokaw getting 75% of the proceeds. Brokaw then specialized in the Hass and often sold out of grafted seedlings since, unlike the Fuerte, Hass yields are year-round and also more plentiful, with bigger fruit, a longer shelf life and richer flavor owing to higher oil content.
By the early 21st century the US avocado industry took in over $1 billion a year from the heavy-bearing, high quality Hass cultivar, which accounted for around 80% of all avocados grown worldwide.