When to Plant Watermelon in Merrill, WI

Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant watermelon in Merrill can be figured out by referring to 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.

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

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 Merrill 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. Any later than that and your watermelon may not have a chance to really do well. If you are starting your watermelon indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Merrill. In the coldest months of winter you should expect an average low temperature of -30°F.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Merrill and it can change quite a bit from year to year. Half of the time in Merrill it frosts late in the year after May 15 so always be ready to protect your watermelon in the event of a late frost.

USDA Zone Info for Merrill

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 Merrill

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