When can I plant Dahlias in Zone 6b

One of the first steps we take when we are making a decision about our gardening schedule is find our USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for our area.

One way of getting a good idea when it's the best time to plant dahlias is to refer to the USDA zone info for Zone 6b.


Planting Calendar for Dahlias

Frost tolerance for dahlias: Not tolerant of frost.
When you should plant them: After the last frost.

Dahlias are not cold tolerant which means that you really should wait until it warms up after the last frost has passed before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant dahlias
Possibly ok, but a risky time to plant dahlias
Probably not a good time to plant dahlias

The earliest that you can plant dahlias in Zone 6b 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 really do well. 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 Zone 6b. In the coldest months of winter we can expect an average low temperature of -5°F.

Since the USDA zone info for Zone 6b is not always accurate our actual date of last frost can change quite a bit from year to year. Since half of the time in Zone 6b we get a frost after April 15 be ready to cover your dahlias if we have a surprise late frost.

USDA Zone Info for Zone 6b

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 Low0°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 Zone 6b

You may be interested in our other planting guides for Zone 6b.