Summer squash appears in many different fruit shapes and colors:
- Scallop or Patty Pan is round and flattened like a plate with scalloped edges, usually white but sometimes yellow or green.
- Constricted neck is thinner at the stem end than the blossom end, classified as either "crookneck" or "straightneck" depending on if the stem end is straight or bent, and is usually yellow.
- Cylindrical to club-shaped Italian marrows, such as zucchini, cocozelle and caserta, are usually shades of green, but may be yellow or nearly white.
The varietal selection of summer squash has markedly changed in recent years and the number of varieties offered has greatly expanded as the result of new interest, hybridization and introduction of disease resistance. The number of varieties is staggering. Recommended varieties of summer squash include:
Zucchini (Open Pollinated)
- Black Zucchini (best known summer squash; greenish black skin, white flesh)
- Black Beauty (slender, with slight ridges, dark black-green)
- Cocozelle (dark green overlaid with light green stripes; long, very slender fruit)
- Vegetable Marrow White Bush (creamy greenish color, oblong shape)
- Aristocrat (All America Selection winner; waxy; medium green)
- Chefini (AAS winner; glossy, medium dark green)
- Classic (medium green; compact, open bush)
- Elite (medium green; lustrous sheen; extra early; open plant)
- Embassy (medium green, few spines, high yield)
- President (dark green, light green flecks; upright plant)
- Spineless Beauty (medium dark green; spineless petioles)
Golden Zucchini (hybrid)
- Gold Rush (AAS winner, deep gold color, superior fruit quality, a zucchini not a straightneck)
- Early Yellow Summer Crookneck (classic open-pollinated crookneck; curved neck; warted; heavy yields)
- Sundance (hybrid; early; bright yellow, smooth skin)
- Early Prolific Straightneck (standard open-pollinated straightneck, light cream color, attractive straight fruit)
- Goldbar (hybrid; golden yellow; upright, open plant)
- White Bush Scallop (old favorite Patty Pan type, very pale green when immature, very tender)
- Peter Pan (hybrid, AAS winner, light green)
- Scallopini (hybrid, AAS winner)
- Sunburst (hybrid, bright yellow, green spot at the blossom end)
- Butter Blossom (an open-pollinated variety selected for its large, firm male blossoms; fruit may be harvested like summer squash, but remove female blossoms for largest supply of male blossoms)
- Gourmet Globe (hybrid; globe-shaped; dark green, with light stripes; delicious)
- Sun Drops (hybrid, creamy yellow, unique oval shape, may be harvested as baby with blossoms attached).