Which Avocado Ripens in the Winter?

Winter Varieties

• Two races of avocados are grown in the United States: Guatemalan (Persea americana guatemalensis) and Mexican (Persea americana drymifolia). "Fuerte," a hybrid of the two, sets the standard for the winter crop. Among the other quality winter avocados are "Bacon," a Mexican variety and similar in size to "Fuerte," and "Pinkerton," which grows bigger than either and is Guatemalan. Another hybrid, "Zutano," also ripens in the winter but has fibrous fruit and does not measure up to the other winter varieties.

Differences in Avocados

• Generally, avocado trees flourish in U.S. Department of Agriculture plant hardiness zones 8 to 11. Mexican varieties, hardier than Guatemalan, have produced fruit as far north as Charleston, South Carolina. Considered more attractive fruit, Guatemalan avocados are also larger than their Mexican counterparts. Mexican cultivars ripen much quicker, reaching maturity six to eight months after flowering. On the other hand, Guatemalan varieties take 12 to 18 months to be ready for harvest. Each avocado variety, regardless of race, has flowers classified as type A or type B. Although the flowers of the avocado are perfect, with both male and female properties, type A becomes receptive to pollen in the morning and sheds pollen the following afternoon. Type B receives pollen in the afternoon, then sheds pollen the next morning. For best production, plant one of each type together for cross-pollination. "Fuerte," "Bacon" and "Zutano" have type B flowers, while "Pinkerton" produces type A.

Growing Avocados

• Avocado trees can be demanding. They need plenty of space, as they can grow to 60 feet tall, with highly competitive roots that may choke out anything planted nearby. In addition, foliage becomes so dense that you cannot garden under the tree, and it sheds leaves throughout the year. If these facts do not deter your interest in growing the luscious fruit, plant in full sun and well-draining soil. Water deeply on a regular basis, but allow the soil to dry out between waterings. While they are young, feed only lightly, but give mature trees 1 pound of nitrogen per year, split into two or more feedings in spring and summer. One of the greatest threats to avocados, especially in California, is Phytophthora root rot. Mulching with fallen leaves and adding gypsum to the soil can suppress the fungal disease.

Avocado Harvest

• Pick avocados when green and firm. Allow them to ripen off the tree, or they become mushy and develop an unpleasant taste. Mexican varieties discolor quickly, so consume them as soon as possible. Guatemalan types can be refrigerated for up to six weeks. Kept at room temperature, avocados ripen in four to seven days. Wrapping the fruit in newspaper or a closed paper bag, with small holes punched in it, can speed up the ripening process. Once ripe, refrigerate to store for another few days.