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.

A way of estimating when to plant dahlias is to refer to the USDA zone info for Cary.

Planting Calendar for Dahlias

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

Since dahlias are not cold tolerant it's necessary to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant dahlias in Cary 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 dahlias and expect a good harvest is probably August. You probably don't want to wait any later than that or else your dahlias may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your dahlias indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Cary. It might get as low as 5°F during the coldest months of winter.

Since the USDA zone info for Cary may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Cary there is a last frost after April 15 be ready to cover your dahlias if you have a late frost.

USDA Zone Info for Cary

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Cary

You may be interested in your other planting guides for Cary.