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If properly cured and stored, winter squash can be stored for several months.

There are many kinds of squash, and the best time to harvest each is different. In particular, the winter squash group, which includes acorn, butternut, spaghetti, and other squash with hard mature rinds, can be difficult to know when to pick. Winter squash also has a longer shelf life (and in some cases better flavor) when properly cured. Learn how and when to pick these squash and how to treat them after harvest to get the most enjoyment from your crop.

Winter squash are separated from summer squash on the basis that they are harvested when mature and will last into the winter if treated properly. Summer squash such as yellow straight type, yellow crookneck and zucchini are harvested when immature and enjoyed through the midsummer months.

Judging when a winter squash is mature is the difficult part. One general rule is to wait until the skin has hardened to the point where it cannot easily be punctured. Use a fingernail or butter knife to check the skin tenderness.

The next telltale signs of maturity are size and color. This varies with each variety, but in general the squash should be about the size and color of what you would expect to see at the store or farmers market. Also, the color of the squash where it contacts the ground should change. This is known as the “ground spot.”

Always harvest winter squash before frost and freezing temperatures arrive and store them in a location that stays above freezing.

Leave the stem attached. Most guides recommend leaving about 2 inches. Stems that are cut much shorter or break away at the connection point from the squash can create an entry point for decay organisms. Use pruning shears or an old serrated knife to cut stems cleanly.

Wipe off or rinse squash after harvest to remove any soil or plant debris that is stuck to the surface.

Recommended curing times vary widely with the source. The Kansas Garden Guide, produced by K-State Research and Extension, recommends curing winter squash by placing them in a warm, dry location for two to three weeks. Ideal temperature for curing is 70 to 80 degrees. Ensure good air circulation by placing squash in single layers on racks if possible. This process will help the skin harden even more to protect the edible fruit inside.

After curing, move squash to a cool (50 to 60 degrees) and dry location for long-term storage. They can store for several months depending on the variety and conditions.

More specific recommendations:

Acorn squash: The skin should be deep green and the ground spot should be dark orange or golden. They can be eaten right after harvest or cured and stored.

Butternut squash: Skin color should be tan to cream, and it should lose the green tint it had earlier in the season. The ground spot will be lighter or white. Cure for best flavor. Cured and properly stored butternut squash will last for several months.

Spaghetti squash: These are yellow to orange at maturity and lose their green tint like butternut squash. The ground spot should be pale yellow to white. They can be eaten right away or cured for longer storage life.

Squash bugs, squash vine borers and cucumber beetles may also be killing vines now. Leave squash attached to vines as long as possible to ensure maturity. If harvesting early, the squash can still be eaten but will have a shorter shelf life.

— Jennifer Smith works in regulatory horticulture and has worked as a horticulturist for various government entities. She has experience in landscape design and maintenance and as an educator.