One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Denver you can estimate when it's the best time to plant celosia by reviewing the USDA zone info.

Planting Calendar for Celosia

Frost tolerance for celosia:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's probably a bad idea to plant celosia until after the last frost has passed because they require warm weather.

The earliest that you can plant celosia in Denver 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 celosia and expect a good harvest is probably August. If you wait any later than that and your celosia may not have a chance to grow to maturity. You can get started a little bit earlier by starting your celosia indoors.

Last Frost Date

In Denver the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Denver is just an average and the actual date of last frost changes from year to year. Half of the time in Denver you get a frost after April 15 so make sure that you are ready to cover your celosia in the event of one of those late frosts.

USDA Zone Info for Denver

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 Denver

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