One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant achillea in Zone 2a can be determined 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.

Achillea are one of those plants that can tolerate quite a bit of cold weather which tells us that you can start planting them much earlier than plants that are more sensitive to the cold.

The earliest that you can plant achillea in Zone 2a is April. However, you really should wait until May 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. If you wait any later than that and 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

The average date of last frost is May 15 in Zone 2a. You can expect an average low temperature of -50°F in the coldest months of winter.

Since the USDA zone info for Zone 2a is not always accurate the actual date of last frost changes from year to year. Half of the time in Zone 2a last frost occurs after May 15 so make sure that you are prepared to cover your achillea if you have one of those late frosts.

USDA Zone Info for Zone 2a

Here is the info for USDA Zone 2a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	August 15
Lowest Expected Low	-50°F
Highest Expected Low	-45°F

This means that on a really cold year, the coldest it will get is -50°F. On most years you should be prepared to experience lows near -45°F.

Plants to Grow in Zone 2a

You may be interested in your other planting guides for Zone 2a.