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

By using the USDA zone info for Columbus it's a good idea to figure out when it's a good idea to plant dahlias.

Planting Calendar for Dahlias

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

Since dahlias are not cold tolerant it is necessary to wait until after the last frost before you can plant them.

The earliest that you can plant dahlias in Columbus 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 really do well. You can get started a little bit earlier by starting your dahlias indoors.

Last Frost Date

On average all chance of frost has passed is on March 15 in Columbus. 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 may not be accurate from year to year because it is based on the USDA zone info for Columbus and it will vary from year to year. Since half of the time in Columbus last frost occurs after March 15 be ready to cover your dahlias in the event of a surprise late frost.

USDA Zone Info for Columbus

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Columbus

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