One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of making a decision about when it's the best time to plant dianthus is to examine the USDA zone info for Columbus.

Planting Calendar for Dianthus

Frost tolerance for dianthus:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant dianthus a little earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant dianthus in Columbus is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant dianthus and expect a good harvest is probably September. You probably don't want to wait any later than that or else your dianthus may not have a chance to really do well. If you are starting your dianthus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Columbus. In the coldest months of winter you can expect an average low temperature of -20°F.

Since the USDA zone info for Columbus is an average the actual date of last frost will vary from year to year. Since half of the time in Columbus there is a last frost after April 15 be ready to cover your dianthus if you have one of those late frosts.

USDA Zone Info for Columbus

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°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.