When to Plant Dahlias in Hamilton, OH

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

By checking out the USDA zone info for Hamilton it's a good idea 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 because they require warm weather.

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 Hamilton 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. If you are starting your dahlias indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Hamilton the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Hamilton and it is different every year. Since half of the time in Hamilton you get a frost after April 15 be ready to cover your dahlias if you have a late frost.

USDA Zone Info for Hamilton

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-10°F
Highest Expected Low-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Hamilton

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