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

It's possible to estimate when to plant dahlia by checking out the USDA zone info for New Haven.

Planting Calendar for Dahlia

Frost tolerance for dahlia:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's not a good idea to plant dahlia until after the last frost because they require warm weather.

The earliest that you can plant dahlia 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 dahlia and expect a good harvest is probably August. Any later than that and your dahlia may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your dahlia indoors.

Last Frost Date

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

Since the USDA zone info for New Haven is just an average the actual date of last frost changes 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 dahlia 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.