When to Plant Watermelon in Sammamish, WA

One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Sammamish should be reviewed to figure out when it's possible to plant watermelon.


Planting Calendar for Watermelon

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

You should not plant watermelon until after all chance of frost has passed because they are not cold tolerant.

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

The earliest that you can plant watermelon in Sammamish 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. If you wait any later than that and your watermelon may not have a chance to really do well. You can get started a little bit earlier by starting your watermelon indoors.

Last Frost Date

In Sammamish the average date of last frost happens on March 15. You should expect an average low temperature of 15°F in the coldest months of winter.

Since the USDA zone info for Sammamish is just an average the actual date of last frost will vary from year to year. Half of the time in Sammamish it frosts late in the year after March 15 so make sure that you are prepared to protect your watermelon in the event of a surprise late frost.

USDA Zone Info for Sammamish

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)March 15
Average Date of First Frost (fall)November 15
Lowest Expected Low15°F
Highest Expected Low20°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 20°F.

Plants to Grow in Sammamish

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