One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to figure out when it's possible to plant gladiolus by using the USDA zone info for Columbus.

Planting Calendar for Gladiolus

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

Since gladiolus 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 plants that might not handle the cold.

The earliest that you can plant gladiolus 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 gladiolus and expect a good harvest is probably August. Any later than that and your gladiolus may not have a chance to really do well. You can get started a couple of weeks earlier by starting your gladiolus indoors.

Last Frost Date

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

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 there is a last frost after April 15 so just be sure to be ready to protect your gladiolus if you have a surprise late frost.

USDA Zone Info for Columbus

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 Columbus

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