The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By looking at the USDA zone info for New Haven it's a good idea to determine when to plant hardy hibiscus.

Planting Calendar for Hardy Hibiscus

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

You can plant hardy hibiscus a lot earlier in the year because they are very cold tolerant.

The earliest that you can plant hardy hibiscus 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 hardy hibiscus and expect a good harvest is probably September. Any later than that and your hardy hibiscus may not have a chance to really do well. You can get started a couple of weeks earlier by starting your hardy hibiscus indoors.

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.

Since the USDA zone info for New Haven is just an average 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 hardy hibiscus if you have 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.