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 Boulder you can determine when it's the best time to plant cantaloupes by reviewing the USDA zone info.

Planting Calendar for Cantaloupes

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

Since cantaloupes are not cold tolerant you need to wait until after the last frost has passed before you can plant them.

The earliest that you can plant cantaloupes in Boulder 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 cantaloupes and expect a good harvest is probably August. Any later than that and your cantaloupes may not have a chance to fully mature. You can get started a little bit earlier by starting your cantaloupes indoors.

Last Frost Date

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

Since the USDA zone info for Boulder is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Boulder you get surprised by a frost after April 15 be ready to cover your cantaloupes if you have one of those late frosts.

USDA Zone Info for Boulder

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 Boulder

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