One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In New Haven you can estimate when it's a good idea to plant liatris by checking out the USDA zone info.

Planting Calendar for Liatris

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

Liatris can survive in a bit of cold which means that you can plant them a lot earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant liatris 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 liatris and expect a good harvest is probably September. Any later than that and your liatris may not have a chance to grow to maturity. If you are starting your liatris indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in New Haven. It might get as low as -10°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for New Haven and it will vary from year to year. Since half of the time in New Haven you get a frost after April 15 be ready to protect your liatris if you have 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.