One of the first steps you take when you are estimating 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.

By checking out the USDA zone info for Glen Carbon it's possible to determine when to plant marigold.

Planting Calendar for Marigold

Frost tolerance for marigold:	Not tolerant of frost.
When to plant:	After the last frost.

You can not plant marigold until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant marigold in Glen Carbon is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant marigold and expect a good harvest is probably August. Any later than that and your marigold may not have a chance to fully mature. Starting your marigold indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Glen Carbon the average date of last frost happens on April 15. You should expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Glen Carbon is not always accurate the actual date of last frost changes from year to year. Half of the time in Glen Carbon you get surprised by a frost after April 15 so make sure that you are ready to cover your marigold if you have one of those late frosts.

USDA Zone Info for Glen Carbon

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 Glen Carbon

You may be interested in your other planting guides for Glen Carbon.