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.

A common way of determining when it's possible to plant achillea is to consult the USDA zone info for Collinsville.

Planting Calendar for Achillea

Frost tolerance for achillea:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since achillea are very cold tolerant you can plant them a lot earlier in the year than other plants that might not handle the cold.

The earliest that you can plant achillea in Collinsville 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 achillea and expect a good harvest is probably September. You probably don't want to wait any later than that or else your achillea may not have a chance to fully mature. You can get started a few weeks earlier by starting your achillea indoors.

Last Frost Date

In Collinsville the average date of last frost happens on April 15. You should expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Collinsville is just an average the actual date of last frost is different every year. Since half of the time in Collinsville last frost occurs after April 15 be ready to cover your achillea in the event of a surprise late frost.

USDA Zone Info for Collinsville

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Collinsville

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