Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can estimate when it's the best time to plant achillea in Wahpeton by looking at the USDA zone info.

Planting Calendar for Achillea

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

You can plant achillea much earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant achillea in Wahpeton 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. Any later than that and your achillea may not have a chance to grow to maturity. If you are starting your achillea indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on May 15 in Wahpeton. In the coldest months of winter you can expect an average low temperature of -30°F.

Since the USDA zone info for Wahpeton is not always accurate the actual date of last frost is different every year. Since half of the time in Wahpeton it frosts late in the year after May 15 be ready to cover your achillea if you have a surprise late frost.

USDA Zone Info for Wahpeton

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Wahpeton

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