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

In Commerce City you can figure out when it's a good idea to plant purple coneflower by looking at the USDA zone info.

Planting Calendar for Purple Coneflower

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

You can plant purple coneflower just a tiny bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant purple coneflower in Commerce City 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 purple coneflower and expect a good harvest is probably August. Any later than that and your purple coneflower may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your purple coneflower indoors.

Last Frost Date

In Commerce City 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 Commerce City is an average and the actual date of last frost is different every year. Half of the time in Commerce City there is a last frost after April 15 so just be sure to be ready to protect your purple coneflower in the event of one of those late frosts.

USDA Zone Info for Commerce City

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 Commerce City

You may be interested in your other planting guides for Commerce City.