When to Plant Dahlias in Mount Vernon, MO

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.

The earliest that you can plant dahlias in Mount Vernon can be figured out by reviewing the USDA zone info.


Planting Calendar for Dahlias

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

You can not plant dahlias until after the last frost has passed 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 Mount Vernon 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 fully mature. You can get started a couple of weeks earlier by starting your dahlias indoors.

Last Frost Date

In Mount Vernon the average date of last frost happens on April 15. You can expect an average low temperature of -10°F in the coldest months of winter.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Mount Vernon and it is different every year. Since half of the time in Mount Vernon you get surprised by a frost after April 15 be ready to protect your dahlias in the event of a late frost.

USDA Zone Info for Mount Vernon

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 Mount Vernon

You may be interested in your other planting guides for Mount Vernon.