Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Columbus can be used to estimate when you can plant lobelia.

Planting Calendar for Lobelia

Frost tolerance for lobelia:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since lobelia are one of those plants that can tolerate quite a bit of cold weather you can plant them a lot earlier in the year than other plants that might not handle the cold.

The earliest that you can plant lobelia 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 lobelia and expect a good harvest is probably September. You probably don't want to wait any later than that or else your lobelia may not have a chance to fully mature. Starting your lobelia indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Always keep in mind that USDA zone info for Columbus is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Columbus last frost occurs after April 15 be ready to cover your lobelia if you have a late frost.

USDA Zone Info for Columbus

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°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 -10°F.

Plants to Grow in Columbus

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