One of the best tools that you have as gardeners to help us determine 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.

You can figure out when it's the best time to plant echinacea in Thornton by checking out 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.

Echinacea do ok in moderate cold which tells us that you can plant them slightly earlier than more sensitive plants.

The earliest that you can plant echinacea in Thornton 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. You probably don't want to wait any later than that or else your echinacea may not have a chance to grow to maturity. Starting your echinacea indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Thornton. It might get as low as -15°F during the coldest months of winter.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Thornton and it changes from year to year. Since half of the time in Thornton you get surprised by a frost after April 15 be ready to protect your echinacea in the event of one of those late frosts.

USDA Zone Info for Thornton

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 Thornton

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