The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's a good idea to estimate when it's possible to plant lobelia by referring to the USDA zone info for Granite City.

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 very cold tolerant you can plant them much earlier in the year than other plants that might not handle the cold.

The earliest that you can plant lobelia in Granite City 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. Any later than that and your lobelia may not have a chance to grow to maturity. Starting your lobelia indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Granite City the average date of last frost happens on April 15. It might get as low as -5°F during the coldest months of winter.

It's important to remember that USDA zone info for Granite City is just an average and the actual date of last frost changes from year to year. Half of the time in Granite City you get a frost after April 15 so be sure to be ready to cover your lobelia if you have a late frost.

USDA Zone Info for Granite City

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Granite City

You may be interested in your other planting guides for Granite City.