One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. 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 looked at to figure out 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.

Achillea can survive in quite a bit of cold which tells us that you can plant them quite a bit 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. Any later than that and your achillea may not have a chance to really do well. You can get started a little bit earlier by starting your achillea indoors.

Last Frost Date

The average date of last frost is April 15 in New Haven. You can expect an average low temperature of 0°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 will vary from year to year. Since half of the time in New Haven you get surprised by a frost after April 15 be ready to cover your achillea in the event of a late frost.

USDA Zone Info for New Haven

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°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.