One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. 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 Frederick should be reffered to in order to estimate when you can plant marigold.

Planting Calendar for Marigold

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

Marigold require warm weather which tells us that you have to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant marigold in Frederick 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. If you wait any later than that and your marigold may not have a chance to grow to maturity. If you are starting your marigold indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Frederick. You can expect an average low temperature of -5°F in the coldest months of winter.

Keep in mind that USDA zone info for Frederick is an average and the actual date of last frost changes from year to year. Half of the time in Frederick it frosts late in the year after April 15 so always be ready to cover your marigold in the event of a surprise late frost.

USDA Zone Info for Frederick

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 Frederick

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