Ohio State University Extension Fact Sheet Horticulture and Crop Science 2021 Coffey Rd., Columbus, Ohio 43210-1086 Growing Squash and Pumpkins in the Home Garden HYG-1620-93 Ted W. Gastier History and Taxonomy Squash and pumpkins will be discussed together because their cultural requirements are similar and because of the great confusion in differentiating between the two. There is also confusion about the origin of pumpkins and squash. T.W. Whitaker and G.W. Bohn presented evidence in 1950 that five species of Cucurbita, that are known as pumpkins and squash, originated in the Americas. Whitaker and Bohn also defined the terms pumpkin, summer squash, and winter squash as follows: Pumpkin-the edible fruit of any species of Cucurbita, used when ripe as a table vegetable or in pies; flesh is somewhat coarse and/or strongly flavored, hence is not generally served as a baked vegetable. Summer Squash-The edible fruit of any species of Cucurbita, commonly C. pepo, used when immature as a table vegetable. Winter Squash-The edible fruit of any species of Cucurbita used when ripe as a table vegetable or in pies; flesh is usually fine-grained and of mild flavor, hence is suitable for baking. Climate Most of the seeds of pumpkin and squash will not germinate satisfactorily in cold soil, and the plants 1 of 5 5/17/09 8:33 PM
are injured by light frosts. Planting should be delayed until the soil has warmed to 68 degrees F at a depth of four inches and the danger of frost has passed. The use of summer squash transplants should be considered if early harvest is important. Fertilizer and Lime Fertilizer and lime applications are best based on soil test results. Soil sample bags, forms, and instructions are available from your county Extension office. General recommendations, when using black plastic mulch, would be one pound of actual nitrogen, two pounds of phosphorus (P 2 O 5 ) and three pounds of potash (K 2 O) per 1,000 square feet. On bare ground, increase the amount of nitrogen by 25 percent. This would best be done as a sidedress application when vines begin to run. Lime should be applied only if indicated by a soil test so as to maintain a ph between 6.5 and 6.8. Culture The use of black plastic mulch will conserve moisture and help control weeds in the row. Spacing of the plants or seeds in the row depends on the growth habit of the vegetable. For bush type squash and pumpkins, hills of two plants should be spaced three to four feet apart with rows on four to five foot centers. For vining types, hills of two plants should be spaced five feet apart with rows on seven foot centers. The vining types of squash and pumpkins need the extra space and will invade even more space if allowed, so plan and plant accordingly. Insects and Diseases Important insect pests of pumpkin and squash are the squash bug, squash vine borer, cucumber beetle, and aphids. Important diseases are powdery mildew, downy mildew, angular leaf spot, black rot and gummy stem blights, mosaic viruses, and bacterial wilt. For assistance, consult your county Extension agent for the latest recommendations. Pollination Home gardeners and others frequently become confused because many blossoms do not set fruit. They need to understand that the male and female parts are in separate flowers and only the female flowers produce fruits. Harvesting Summer squashes of all types and varieties should be harvested when they reach a size of four to six inches long and 1.5 to 2.5 inches in diameter. This ensures high-quality fruit and additional fruit production. High-quality winter squashes and pumpkins are associated with maturity, so they should not be harvested until they are fully ripe. Fruits subjected to a hard frost will not keep, so harvest should be completed before cold weather. 2 of 5 5/17/09 8:33 PM
A portion of the stem is usually left attached to the pumpkin or squash at harvest time. Halloween pumpkins are most attractive when a stem or "handle" is carefully allowed to remain. Storage of Winter Squash and Pumpkins Store only those fruit that are free of cuts, wounds, and insect or disease damage. Immediately after harvest, the fruit should undergo a ripening or curing process to harden the shell. A curing period of about two weeks at 75 to 85 degrees F with good circulation is desirable. Storage should then be at 50 to 70 degrees F with humidity between 50 and 70 percent. Varieties Based on university trials, the following cultivated varieties or "cultivars" are recommended: Summer Squash (summer squash are bush types) Straightneck Multi-pick Precious Crookneck Superset Medallion Sundance Zucchini (golden color) Gold Rush Zucchini (green color) Ambassador Spineless Beauty Patty Pan Peter Pan Sunburst Winter Squash (vining type, unless noted) Acorn Table Queen Table King (bush) Table Ace (semi-bush) Table Queen, ebony strain Cream of the Crop (bush) Butternut 3 of 5 5/17/09 8:33 PM
Zenith Ultra Butternut Ponca (semi-bush) Puritan Waltham Butternut Vegetable Spaghetti Vegetable Spaghetti Tivoli (bush) Buttercup Burgess Strain Sweet Mama Hubbard Golden Hubbard (red-orange) Green Warted Hubbard (blackish-green) Blue Hubbard (light blue-gray) Turk's Turban Turk's Turban Sweet Potato Squash Delicata Delicata JS Pumpkins Miniature Pumpkin Munchkin Jack Be Little Baby Bear (1993 All American Selection) Baby Boo (white) Halloween Pumpkin Howden Jackpot Spirit Small Sugar (also used in pies) Frosty (bush) Connecticut Field Ghost Rider Jumpin Jack Pankow Field (upright) Autumn Gold Happy Jack 4 of 5 5/17/09 8:33 PM
Big Moon (pink-cream color) Rouge Vif D'Etampes - deep red Extra Large Halloween Pumpkin Prizewinner Big Max Atlantic Giant White Halloween Pumpkin Baby Boo Lumina (larger) Pumpkins Suitable for Painting Baby Boo Munchkin Lumina Baby Pam Gremlin Naked, Hulless, Edible Seeded Pumpkin (seeds for snacks, roasted/raw) Trick or Treat The author gratefully acknowledges James D. Utzinger, William M. Brooks, and E.C. Wittmeyer on whose original fact sheet this is based. This fact sheet was reviewed by Eugene Wittmeyer, professor emeritus, The Ohio State University, Department of Horticulture, and Marianne Riofrio, Extension Associate, The Ohio State University. All educational programs conducted by Ohio State University Extension are available to clientele on a nondiscriminatory basis without regard to race, color, creed, religion, sexual orientation, national origin, gender, age, disability or Vietnam-era veteran status. Keith L. Smith, Associate Vice President for Ag. Adm. and Director, OSU Extension. TDD No. 800-589-8292 (Ohio only) or 614-292-1868 Ohioline Search Fact Sheets Bulletins 5 of 5 5/17/09 8:33 PM