When to Plant Dahlias in Hartford, CT

One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Hartford should be used to figure out when it's possible to plant dahlias.


Planting Calendar for Dahlias

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

It's probably not a good idea to plant dahlias until after the last frost has passed because they are not cold tolerant.

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 Hartford 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 grow to maturity. You can get started a couple of weeks earlier by starting your dahlias indoors.

Last Frost Date

On average the last frost is on April 15 in Hartford. In the coldest months of winter you should expect an average low temperature of -5°F.

Always keep in mind that USDA zone info for Hartford may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Hartford it frosts late in the year after April 15 so make sure that you are ready to protect your dahlias in the event of a late frost.

USDA Zone Info for Hartford

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 Hartford

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