When to Plant Squash in Washington, IL

Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Washington should be looked at to figure out when to plant squash.


Planting Calendar for Squash

Frost tolerance for squash: Not tolerant of frost.
When to plant: After the last frost has passed.

Since squash require warm weather you need to wait until after the last frost when the weather gets warmer before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant squash
Possibly ok, but a risky time to plant squash
Probably not a good time to plant squash

The earliest that you can plant squash in Washington is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant squash and expect a good harvest is probably August. If you wait any later than that and your squash may not have a chance to grow to maturity. If you are starting your squash indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Washington the average date of last frost happens on April 15. You can expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Washington is just an average and the actual date of last frost will vary from year to year. Since half of the time in Washington it frosts late in the year after April 15 be ready to protect your squash if you have a late frost.

USDA Zone Info for Washington

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-15°F
Highest Expected Low-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Washington

You may be interested in your other planting guides for Washington.