Summer squash includes those varieties which are harvested while still immature and when the entire squash is tender and edible. They include the yellow Crookneck, the large Straight neck, the greenish-white Patty Pan, and the slender green Zucchini. Some of these squash are available at all times of the year.
Look for squash that are tender and well developed, firm, and fresh-appearing. You can identify a tender squash, because the skin is glossy instead of dull, and it is neither hard nor tough. Avoid stale or over mature squash, which will have a dull appearance and a hard, tough surface. Such squash usually have enlarged seeds and dry, stringy flesh. Also avoid squash with discolored or pitted areas.