One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant watermelon in Duluth should be determined by using the USDA zone info.

Planting Calendar for Watermelon

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

Watermelon require warm weather which tells us that you really should wait until it warms up after the last frost before you can plant them.

The earliest that you can plant watermelon in Duluth is May. However, you really should wait until June 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 fully mature. Starting your watermelon indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on May 15 in Duluth. You can expect an average low temperature of -30°F in the coldest months of winter.

Since the USDA zone info for Duluth is an average the actual date of last frost changes from year to year. Since half of the time in Duluth last frost occurs after May 15 be ready to cover your watermelon if you have a late frost.

USDA Zone Info for Duluth

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Duluth

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