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.

In Somerset you can determine when it's a good idea to plant achillea 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 a lot 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 Somerset 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 little bit earlier by starting your achillea indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Somerset. You can expect an average low temperature of -15°F in the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Somerset and it is different every year. Half of the time in Somerset you get surprised by a frost after April 15 so always be ready to cover your achillea if you have a surprise late frost.

USDA Zone Info for Somerset

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Somerset

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