The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant marigold in Zone 6a should be determined by checking out the USDA zone info.

Planting Calendar for Marigold

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

It's not a good idea to plant marigold until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant marigold in Zone 6a 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 couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Zone 6a. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Zone 6a is just an average the actual date of last frost will vary from year to year. Since half of the time in Zone 6a you get a frost after April 15 be ready to cover your marigold in the event of one of those late frosts.

USDA Zone Info for Zone 6a

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 Zone 6a

You may be interested in your other planting guides for Zone 6a.