The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Harvard you can determine when to plant watermelon 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 when the weather gets warmer.

Watermelon require warm weather which means 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 Harvard 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. If you are starting your watermelon indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Harvard. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Harvard is an average the actual date of last frost will vary from year to year. Since half of the time in Harvard you get surprised by a frost after April 15 be ready to cover your watermelon in the event of a surprise late frost.

USDA Zone Info for Harvard

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 Harvard

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