Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Trenton you should be able to figure out when it's possible to plant marigold.

Planting Calendar for Marigold

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

It's probably a bad idea to plant marigold until after the last frost because they do not do well in cold weather.

The earliest that you can plant marigold in Trenton 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 fully mature. 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 Trenton. It might get as low as -5°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Trenton is just an average and the actual date of last frost will vary from year to year. Half of the time in Trenton you get surprised by a frost after April 15 so always be ready to cover your marigold in the event of one of those late frosts.

USDA Zone Info for Trenton

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 Trenton

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