One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Washington you can determine when you can plant watermelon by looking at the USDA zone info.

Planting Calendar for Watermelon

Frost tolerance for watermelon:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

You really shouldn't plant watermelon until after the last frost because they require warm weather.

The earliest that you can plant watermelon 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 watermelon and expect a good harvest is probably August. Any later than that and your watermelon may not have a chance to fully mature. If you are starting your watermelon indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is March 15 in Washington. It might get as low as 10°F during 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 changes from year to year. Since half of the time in Washington there is a last frost after March 15 be ready to cover your watermelon if you have one of those late frosts.

USDA Zone Info for Washington

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

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

Plants to Grow in Washington

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