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.

The USDA zone info for New Haven can be reviewed to figure out when it's the best time 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 earlier in the year than other plants that might not handle the cold.

The earliest that you can plant achillea in New Haven 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 grow to maturity. You can get started a little bit earlier by starting your achillea indoors.

Last Frost Date

On average the last frost is on April 15 in New Haven. You should expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for New Haven may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in New Haven you get a frost after April 15 be ready to protect your achillea in the event of a surprise late frost.

USDA Zone Info for New Haven

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in New Haven

You may be interested in your other planting guides for New Haven.