When to Plant Marigold in Trenton, MO

The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant marigold in Trenton can be figured out by looking at 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 probably a bad idea to plant marigold until after the last frost has passed because they are not cold tolerant.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant marigold
Possibly ok, but a risky time to plant marigold
Probably not a good time to plant marigold

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. You can get started a few weeks earlier by starting your marigold indoors.

Last Frost Date

In Trenton the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Trenton and it changes from year to year. Since half of the time in Trenton it frosts late in the year after April 15 be ready to cover your marigold in the event of a surprise late frost.

USDA Zone Info for Trenton

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 Trenton

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