Winter squashes are grown in the summer for winter storage. There are numerous types, belonging to a number of closely related species, and the range of size, coloring and skin types is nothing short of astounding. They are also a fantastic source of beta-carotene and other essential nutrients.
We put winter squash in the second part of our rotation. The planting method is essentially the same as for other members if the squash family: plant a single row of squashes down the center of a three-foot bed, spacing the plants every two feet. It’s best to choose a bed at the edge of your garden as the plants will run (and having them run out over lawn or common areas saves space in the garden central. In cool climate areas, yields can be increased significantly if you lay drip tubing along the center of the bed, put a shovelful of compost at each planting spot, then cover the bed with black plastic mulch for a week or two before planting.
Once the frost-free date has arrived, we make a small cross-like incision at each lump in the plastic, and press two or three seeds into the compost heaped there. If we have started plants indoors—you can sow the seed two weeks earlier in a large soil block or a 50-cell plug tray—we set one in each spot. Immediately after planting we cover the bed with a floating row cover to keep out flying insect pests, and then turn on the drip irrigation for an hour or so to thoroughly wet the soil around the seed (or plant).
Once the plants flower we remove the covers. From that point on, a few cucumber beetles may find the plants and take up residence, but by then the plants are growing so fast that not even a cuke beetle can hold them back. We used to spray them with a mixture of rotenone and pyrethrum, but eventually decided it was too much trouble for the amount of control we got. Two bigger problems — especially for gardeners below USDA Zone 4 — are squash bugs and squash vine borers, both of which have a hard time surviving the harsh winters of the north. The Brown Marmorated Stink Bug (BMSB) is also becoming a serious pest in the parts of the US where it has become established. With any of these pests, the best control is prevention. Keep the row covers on until flowering; look closely for eggs and destroy them.
There are a few new cultivars of winter squash that grow on compact bush plants, but with most of the older types will run ten, twenty, even thirty feet or more, so it makes sense to plant them either at the edge of the garden, so they can run outside its borders, or next to the corn, so the vines can run through the corn patch.
Winter squashes should be left on the vine until frost threatens, or the vines die off. Each cultivar has its own particular signs of ripening based on the color of the fruit, though all must be allowed to firm up their skins so that they will store well. If you have a hard time nicking the skin with your fingernail, the fruit is ready.
After harvest most winter squash should receive a few extra days of curing before being put in storage. Some gardeners wipe the outside of the fruits with a very mild, dilute bleach-and-water solution (10:1) to kill any bacteria that might lead to rot while in storage; for rough skinned types you can dip them in a tub of the solution for a few moments. Though there is some variation among types, if stored at 40˚ to 50˚ F (4˚ to 10˚ C) in a dry, airy place, the fruits of most winter squash and pumpkin cultivars will keep four to six months.