One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The best time to plant echinacea in Castle Rock should be determined by referring to the USDA zone info.

Planting Calendar for Echinacea

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

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

The earliest that you can plant echinacea in Castle Rock 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 echinacea and expect a good harvest is probably August. If you wait any later than that and your echinacea may not have a chance to really do well. If you are starting your echinacea indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Keep in mind that USDA zone info for Castle Rock is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Castle Rock it frosts late in the year after April 15 so be sure to be ready to protect your echinacea in the event of one of those late frosts.

USDA Zone Info for Castle Rock

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 Castle Rock

You may be interested in your other planting guides for Castle Rock.