Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of getting a good idea when you can plant coral bells is to look at the USDA zone info for Denver.

Planting Calendar for Coral Bells

Frost tolerance for coral bells:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since coral bells are one of those plants that can tolerate a little bit of cold weather you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant coral bells in Denver is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant coral bells and expect a good harvest is probably September. Any later than that and your coral bells may not have a chance to grow to maturity. If you are starting your coral bells indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Denver is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Denver last frost occurs after April 15 so be sure to be ready to cover your coral bells if you have a surprise late frost.

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.