One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant dahlias in Zone 2b should be determined by using the USDA zone info.

Planting Calendar for Dahlias

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

You really shouldn't plant dahlias until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant dahlias in Zone 2b is May. However, you really should wait until June 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 really do well. Starting your dahlias indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on May 15 in Zone 2b. It might get as low as -45°F during the coldest months of winter.

Always keep in mind that USDA zone info for Zone 2b may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Zone 2b you get surprised by a frost after May 15 so make sure that you are ready to protect your dahlias if you have one of those late frosts.

USDA Zone Info for Zone 2b

Here is the info for USDA Zone 2b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	August 15
Lowest Expected Low	-45°F
Highest Expected Low	-40°F

This means that on a really cold year, the coldest it will get is -45°F. On most years you should be prepared to experience lows near -40°F.

Plants to Grow in Zone 2b

You may be interested in your other planting guides for Zone 2b.