Pears are in season at different times, depending on the variety and climate. The fruits don't ripen fully on the tree but instead require a ripening period after harvest. Determining the season for your pears requires careful observance of the fruits on the tree. You must also figure in the ripening period necessary for the fruit to determine when the pears will be ready to use.
Late-summer pears are ready to pick in August in warmer climates and September in colder regions. Bartlett, Flemish Beauty and Aurora are just a few varieties of early-maturing pears. These fruits are ready to pick when the fruit is firm and separates easily from the stem. The pears also have small spots on them that darken from white to brown as the fruit reaches maturity. Late-summer pears require some off-the-tree ripening, but they typically ripen more quickly than later-producing pear varieties and are ready for eating in the early fall.
Many of the common grocery-store varieties ripen in the fall, including Bosc and Anjou. These pears ripen in later September and early October in warm climates, and late October in cooler regions. Other later-ripening varieties include El Dorado, Seckel and Comice. Like summer pears, fall pears develop firm fruit and separate from the tree easily once they're mature. Fall pears require a longer ripening period than late-summer varieties once harvested, so although the fruits are harvested in the fall, they're not ready to use until the late fall or early winter.
Summer pears take approximately one week to ripen at room temperature after harvesting. They don't require cold storage, which shortens the ripening time. Fall pears require four weeks of cold storage at a temperature between 32 and 45 degrees Fahrenheit. After cold storage, these pears require another three to five days of storage at room temperature to fully ripen. Though harvested in the fall, the pears aren't ready to eat until four to five weeks after you've picked them from the tree.
Asian pear varieties ripen fully on the tree. They come into season earlier than most other pears. The fruits begin maturing in July in warm climates that rarely experience frost; they're ready for harvest in August or September in colder regions. Pick the pears when they develop their mature color and separate from the tree easily. Color depends on the variety, with russet types turning brown, and green varieties remaining green, except for the spot facing the ground, which turns yellow. A taste test of one or two fruits also indicates when they're ready to pick — the pears become tender and sweet at maturity. Asian pears store well on the tree for two or three weeks, so pick them as you need them once they begin to ripen.