Also known as the alligator pear, the avocado enjoys widespread popularity as a cultivated fruit in tropical areas and in warm regions of the United States. This rich, creamy fruit contains high levels of monounsaturated fat. According to California Rare Fruit Growers, the olive is the only fruit which contains a higher level of oil. Mexican food enthusiasts add avocado to dishes, and children grow plants from the fruit's large single seed.
Growers began cultivating avocados in Mexico and Central and South America before the first Europeans arrived on the American continent. In 1871, the avocado was introduced in California; the state now produces up to 95 per cent of the avocados grown in the United States. The University of Illinois states that the 'Haas' cultivar, now 85 per cent of California's avocado crop, received its patent in 1935.
According to the University of Hawaii Extension, avocados descend from three "races": Mexican, Guatemalan and West Indian. Mexican and Guatemalan races will tolerate brief periods of subfreezing temperatures; West Indian avocados require a warm climate with temperatures remaining above freezing. The popular 'Haas' cultivar descends from the Guatemalan race. Avocado trees produce two types of flowers: type A flowers receive pollen in the morning and shed pollen in the afternoon, while type B flowers undergo an opposite cycle.
Fruit will appear on a grafted avocado plant within 1 to 2 years, while seedlings bear fruit after 8 to 20 years. Avocado trees bloom from January to March; each cluster of 200 to 300 yellow-green flowers produces only two or three fruits. California Rare Fruit Growers, Inc. states that for a successful growing season, an orchard requires cross-pollination between type A and type B flowers. An avocado fruit matures within 5 to 15 weeks, depending on the variety, and will ripen approximately 1 week after harvest.
A mature avocado will change skin colour but remain hard. Harvesting too early or too late can damage the fruit; to prevent blackening from cold damage, harvest before the first frost. Due to the small number of blossoms which produce fruit, and the long time required for fruit to mature, an avocado orchard can require 2 years to recover from an extended cold spell. Mexican avocados tolerate brief cold spells better than other types.
Producers can leave avocados on a tree for an extended period because the fruit ripens after harvest. Commercial producers have plenty of time to harvest their crop, and consumers enjoy a long avocado season at the supermarket. The University of Hawaii notes that in Mexico, the prime season for 'Haas' avocados runs from October to May, with harvests all year.