One of the first steps you take when you are getting a good idea your gardening schedule is find your 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 chrysanthemums by reviewing the USDA zone info.

Planting Calendar for Chrysanthemums

Frost tolerance for chrysanthemums:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since chrysanthemums are barely cold tolerant you can plant them just a tiny bit earlier in the year than other frost tender plants.

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

The last month that you can plant chrysanthemums and expect a good harvest is probably August. Any later than that and your chrysanthemums may not have a chance to fully mature. If you are starting your chrysanthemums indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Denver is just an average the actual date of last frost is different every year. Half of the time in Denver last frost occurs after April 15 so always be ready to cover your chrysanthemums if you have a 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.