Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Jefferson should be read to determine when it's the best time to plant dahlias.

Planting Calendar for Dahlias

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

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

The earliest that you can plant dahlias in Jefferson 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. If you wait any later than that and your dahlias may not have a chance to fully mature. You can get started a few weeks earlier by starting your dahlias indoors.

Last Frost Date

The average date of last frost is April 15 in Jefferson. It might get as low as -20°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Jefferson and it is different every year. Since half of the time in Jefferson there is a last frost after April 15 be ready to cover your dahlias if you have a surprise late frost.

USDA Zone Info for Jefferson

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Jefferson

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