When to Plant Watermelon in Broomfield, CO

The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to figure out when to plant watermelon by referring to the USDA zone info for Broomfield.


Planting Calendar for Watermelon

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

Since watermelon require warm weather you really should wait until after the last frost 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 Broomfield 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 little bit earlier by starting your watermelon indoors.

Last Frost Date

In Broomfield the average date of last frost happens on April 15. You should expect an average low temperature of -10°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Broomfield and it will vary from year to year. Since half of the time in Broomfield you get a frost after April 15 be ready to cover your watermelon if you have a surprise late frost.

USDA Zone Info for Broomfield

Here is the info for USDA Zone 6a.

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

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

Plants to Grow in Broomfield

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