Cucurbita argyrosperma aka Cushaw

Cucurbita argyrosperma is a vine in the gourd family. It grows for one year. People call it cushaw squash, winter squash, or silverseed gourd. Kew gives its native range as Mexico to Nicaragua. It grows in tropical regions with a dry season. People first grew it as a crop in southern Mexico. Growers now raise it in warm temperate and tropical areas. Some garden sources say its wild origin is still unclear.

The vine grows fast and spreads across bare ground. Tendrils help it climb trellises and other supports. Garden plants reach about 1.5 feet [0.46 metres] high. Their spread can reach 15 feet [4.57 metres]. Dark green stems bear large leaves that grow in turn. Each leaf is simple, with one blade rather than leaflets. The leaves have lobes, toothed edges, and heart-shaped bases. Their surfaces feel rough and may have prickly hairs. Each leaf can exceed 0.5 feet [0.15 metres] in length and width.

Each plant bears male and female flowers as separate blooms. Insects pollinate the flowers, and bees help move the pollen. The flowers grow one at a time. They have a funnel shape. Their colour ranges from pale yellow to orange. Missouri Botanical Garden lists bloom time as July to August. Fruits ripen for harvest in fall and vary in shape. Some have long, thick necks and hard, corky stalks. Their skins may have stripes or spots in several colours. Fruits often weigh between 10 and 20 pounds. People use them for food and as fresh or dried decor.

Grow this squash in full sun and a warm site. It needs rich loam that drains well yet holds moisture. Keep the soil moist, but not soaked or full of water. The plant copes with heat but suffers in cool weather. Frost kills it despite its broad listed growing-zone range. Sow outdoors once soil reaches at least 65°F. Set out young plants after the last spring frost. Its wide spread suits large gardens and planting to cover soil. A trellis lets it use space above the ground.

People eat the fruit, seeds, flowers, and leaves. Cooked flesh can go into soups, pies, or bread mixtures. Seeds yield edible oil; people can roast or grind them. Sources also note seed use against worms in the gut. Sprouting seeds contain a toxic substance in the embryo. This is the young plant within the seed. NC State lists the plant as safe for common pets. Wilt, mildew, and blossom-end rot may cause problems. Aphids, beetles, and squash bugs may attack it. Borers, mites, and slugs may also attack it.