Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of determining when you can plant achillea is to look at the USDA zone info for Sioux Falls.

Planting Calendar for Achillea

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

Achillea do well in cold weather which means that you can plant them quite a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant achillea in Sioux Falls 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 achillea and expect a good harvest is probably August. You probably don't want to wait any later than that or else your achillea may not have a chance to grow to maturity. Starting your achillea indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Sioux Falls the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Keep in mind that USDA zone info for Sioux Falls is just an average and the actual date of last frost changes from year to year. Since half of the time in Sioux Falls you get surprised by a frost after May 15 be ready to protect your achillea in the event of one of those late frosts.

USDA Zone Info for Sioux Falls

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Sioux Falls

You may be interested in your other planting guides for Sioux Falls.