One of the first steps you take when you are estimating 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.

One way of figuring out when to plant watermelon is to consult the USDA zone info for Zone 4b.

Planting Calendar for Watermelon

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

Since watermelon are not cold tolerant it's necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant watermelon in Zone 4b 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. 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

In Zone 4b the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -25°F.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Zone 4b and it can change quite a bit from year to year. Since half of the time in Zone 4b there is a last frost after May 15 be ready to protect your watermelon if you have one of those late frosts.

USDA Zone Info for Zone 4b

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Zone 4b

You may be interested in your other planting guides for Zone 4b.