The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Mound can be read to determine when it's possible to plant achillea.

Planting Calendar for Achillea

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

Since achillea do well in cold you can plant them much earlier in the year than more sensitive plants.

The earliest that you can plant achillea in Mound 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 fully mature. You can get started a couple of weeks earlier by starting your achillea indoors.

Last Frost Date

On average the last frost has passed is on May 15 in Mound. You should expect an average low temperature of -25°F in the coldest months of winter.

Just be sure 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 Mound and it can change quite a bit from year to year. Half of the time in Mound you get a frost after May 15 so be sure to be ready to cover your achillea if you have one of those late frosts.

USDA Zone Info for Mound

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 Mound

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