One of the first steps you take when you are making a decision about 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 figure out when you can plant calliopsis by reviewing the USDA zone info.

Planting Calendar for Calliopsis

Frost tolerance for calliopsis:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since calliopsis are not cold tolerant you need to wait until after the last frost has passed before you can plant them.

The earliest that you can plant calliopsis in New Haven 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 calliopsis and expect a good harvest is probably August. Any later than that and your calliopsis may not have a chance to really do well. If you are starting your calliopsis indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In New Haven the average date of last frost happens on April 15. You can expect an average low temperature of -10°F in the coldest months of winter.

It's important to remember 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 is different every year. Half of the time in New Haven you get a frost after April 15 so make sure that you are prepared to cover your calliopsis in the event of one of those late frosts.

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.