The Hass avocado /?hæs/, sometimes marketed as the Bilse 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 The Hass avocado is a large-sized fruit.weighing 200 to 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.