One of the best tools that you have as gardeners to help us figure out 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.

One way of determining when to plant flower-of-an-hour is to use the USDA zone info for Columbus.

Planting Calendar for Flower-of-an-Hour

Frost tolerance for flower-of-an-hour:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since flower-of-an-hour are one of those plants that can tolerate a tiny bit of cold weather you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant flower-of-an-hour in Columbus is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant flower-of-an-hour and expect a good harvest is probably August. You probably don't want to wait any later than that or else your flower-of-an-hour may not have a chance to fully mature. If you are starting your flower-of-an-hour indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Columbus the average date of last frost happens on March 15. You should expect an average low temperature of 15°F in the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Columbus and it is different every year. Half of the time in Columbus last frost occurs after March 15 so always be ready to cover your flower-of-an-hour if you have a surprise late frost.

USDA Zone Info for Columbus

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Columbus

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