One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. 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 you can plant dahlias is to use the USDA zone info for Williamsburg.

Planting Calendar for Dahlias

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

Dahlias do not do well in cold weather which means that it is important to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant dahlias in Williamsburg 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. Any later than that and your dahlias may not have a chance to really do well. If you are starting your dahlias indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

It's important to remember that USDA zone info for Williamsburg is not always accurate and the actual date of last frost is different every year. Since half of the time in Williamsburg it frosts late in the year after April 15 be ready to protect your dahlias if you have one of those late frosts.

USDA Zone Info for Williamsburg

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°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 0°F.

Plants to Grow in Williamsburg

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