One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of estimating when it's the best time to plant marigold is to check out the USDA zone info for Three Rivers.

Planting Calendar for Marigold

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

Since marigold are not cold tolerant you have to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant marigold in Three Rivers 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. You probably don't want to wait any later than that or else your marigold may not have a chance to really do well. You can get started a little bit earlier by starting your marigold indoors.

Last Frost Date

The average date of last frost is April 15 in Three Rivers. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Three Rivers is just an average the actual date of last frost changes from year to year. Half of the time in Three Rivers there is a last frost after April 15 so be sure to be ready to protect your marigold in the event of a surprise late frost.

USDA Zone Info for Three Rivers

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 Three Rivers

You may be interested in your other planting guides for Three Rivers.