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

It's possible to estimate when it's a good idea to plant watermelon by checking out the USDA zone info for Umatilla.

Planting Calendar for Watermelon

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

Since watermelon do not do well in cold weather it is important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant watermelon in Umatilla 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. You probably don't want to wait any later than that or else your watermelon may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your watermelon indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Umatilla. In the coldest months of winter you should expect an average low temperature of 5°F.

Since the USDA zone info for Umatilla is an average the actual date of last frost will vary from year to year. Since half of the time in Umatilla you get a frost after April 15 be ready to protect your watermelon in the event of one of those late frosts.

USDA Zone Info for Umatilla

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Umatilla

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