The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant penstemon in New Haven should be estimated by using the USDA zone info.

Planting Calendar for Penstemon

Frost tolerance for penstemon:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since penstemon do well in moderate cold you can plant them just a bit earlier in the year than more sensitive plants.

The earliest that you can plant penstemon 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 penstemon and expect a good harvest is probably September. Any later than that and your penstemon may not have a chance to grow to maturity. Starting your penstemon indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in New Haven. In the coldest months of winter you should expect an average low temperature of 0°F.

Keep in mind that USDA zone info for New Haven may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in New Haven last frost occurs after April 15 be ready to cover your penstemon if you have 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.