Let's think about Halloween and Thanksgiving, even if it is the middle of July.

That's because winter squashes play important roles during those two fall holidays, and they need to be planted now.

Pumpkin, butternut and other non-native winter-squash seeds take 90 to 120 days to grow, depending on the variety, says master gardener Monica A. Burgan.

"July is a good month to plant stuff like that," says the retired dental-laboratory technician. "The ground is moist and it's warm."

NON-NATIVE SQUASHes

All manner of winter squashes grow happily in the Tucson climate, says Burgan, including hubbard, spaghetti, buttercup and carnival varieties. "They're really basically easy to grow."

Plant seeds no deeper than 2 inches in a mixture of half-dirt and half-compost, Burgan advises. Plant the seeds about 12 to 18 inches apart to accommodate spreading vines.

The plants like Tucson's full sun. Keep the soil moist to a depth of 8 to 12 inches.

Harvest winter squashes when the shell is hard. You can test that by pushing your fingernail against it. If you don't pierce the skin, it's starting to ripen.

At that point you can pick them for carving and other decorating projects. You can also start picking for eating.

Burgan, who plants winter squashes solely for food, raps on the fruit and listens for a hollow sound. That's her cue that it's ripe enough to eat.

She also suggests watching the plant stem. "If the stem off the vine is shrunken up, it's ripe," she says.

NATIVE SQUASHes

Summer rains are the prime time to plant native squashes such as O'odham ha:l, the pumpkinlike Tarahumara and Navajo gray Hubbard. Dig your garden to create a basin that captures rainwater and run-off. Then plant the seeds 1 inch deep in the basin. Like non-native squashes, you'll want to provide plenty of room for the vines to grow out.

Seeds sown in July that receive good seasonal rain will yield squashes starting in late October. The squash harvest can last through December, says J.P. Wilhite, director of distribution for Native Seeds/SEARCH, which grows and collects seeds from heirloom crops grown by regional Native Americans.