Here is a handy reference from the Tennessee State University's Institute of Agriculture website to help you determine when to buy fruit. This list obviously changes slightly depending on where you live in the world (and you can buy anything at anytime these days, so most everything is always AVAILABLE) but this list is still a nice reference to have. If I'd seen this, I wouldn't have bought that bad pear the other day that excited then disappointed me. Below, each fruit name is followed by it's peak season and what to look for when shopping.
Apples: September-May. Good color for variety; firm to touch. Avoid those that are soft and mealy.
Apricots: June-July. Golden yellow; plump; firm. Avoid pale yellow or green, very hard or soft, shriveled and wilted ones.
Avocados: All Year. Yield to gentle pressure; vary in size, shape and color from green to black. Brown markings on skin do not lower quality.
Bananas: All Year. Firm; bruise free; yellow touched with green. If needed, ripen at room temperature.
Blueberries: June-August. Firm; plump; full-colored; bright, clean, fresh appearance.
Cantaloupes: May-September. Color and aroma best guides. Delicate
aroma; thick netting that stands out; yellow-tinged skin under the netting. No evidence of stem at blossom end.
Casaba Melons: July-October. Buttery-yellow, wrinkled rinds, lengthwise furrows.
Cherries: May-June. Fresh appearance; firm; good size for type of cherry.
Coconuts: September-March. Good weight for the size; milk inside still fluid. If no milk, coconuts are spoiled. Avoid ones with moldy or wet-looking eyes.
Cranberries: September-December. Firm; plump; full-colored; bright, clean, fresh appearance.
Crenshaw Melons: July-October. Yellow-gold rind; pleasant aroma.
Figs: July-September. Fairly soft to touch. Use at once, spoils quickly. Sour odor indicates overripe fruit.
Grapefruit: October-June. Firm; well-rounded; heavy for the size; smooth textured. Avoid coarse, puffy, rough-skinned fruit.
Grapes: June-December. Fairly soft; tender; plump. Well-formed clusters with green, pliable stems. Darker varieties are free of green tinge; green grapes have a slight amber blush.
Honeydew Melons: February-October. Creamy, yellow rinds; pleasant aroma.
Kiwi: June-August. Soft to touch, like avocado. Sometimes called Chinese gooseberries.
Lemons: All year. Fairly firm; smooth and glossy-skinned; heavy for size.
Limes: May-October. Heavy for size. Green variety more acidic than yellow.
Mangoes: April-August. Solid and not too soft to touch. Can vary in size from a plum to an apple and in color from yellow to red. Smooth skin often speckled with black. Green mangoes are sometimes used in cooking.
Nectarines: June-September. Plump; fairly fi rm depending on type. Skin color white or yellow with a red blush.
Peaches: June-September. Plump; fairly firm depending on type. Skin color white or yellow with a red blush.
Persian Melons: July-October. Thick webbing; gray-green to brown skin under webbing.
Oranges: November-June. Heavy for size; firm; skins not too rough.
Papayas: All year. Greenish yellow to full yellow in color; flesh gives slightly when fruit pressed in palm of hand.
Pears: August-May. Yields to gentle pressure at stem end. Color ranges from creamy yellow to russet. Ripen at room temperature.
Persimmons: October-January. Firm; shapely; plump; orange-red color; attached stem cap. Handle gently. Looks like a large red tomato in shape and firmness.
Pineapples: February-August. "Piney" aroma; golden yellow; slightly soft. Ripe when leaf is easily removed. Green fruit may not ripen properly. Over-mature fruit may show soft watery darker spots on the base or sides.
Plums: June-September. Plump; full-covered, soft enough to yield to slight pressure. Softening at tip is usually a sign that fruit is mature. Avoid shriveled and hard plums.
Pomegranates: September-November. Thin-skinned; bright purple-red; looks fresh.
Raspberries: March-July. Plump; full-colored; bright, clean, fresh appearance.
Strawberries: June-August. Firm; plump; full-colored; bright, clean, fresh appearance. Should have hull (stem cap) attached when mature.
Tangerines: November-January. Deep orange or yellow; glossy skin.
Tangelos: January-October. Loose skin. Overripe fruit has puffy, dry skin.
Watermelons: May-August. Dull surfaces with cream-colored undersides; symmetrical shape.