When to Plant Marigold in Johnstown, CO

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

The USDA zone info for Johnstown can be used to figure out when it's the best time to plant marigold.


Planting Calendar for Marigold

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

You can not plant marigold until after all chance of frost has passed because they require warm weather.

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 Johnstown 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 grow to maturity. Starting your marigold indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Johnstown the average date of last frost happens on April 15. You should expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Johnstown and it will vary from year to year. Since half of the time in Johnstown you get a frost after April 15 be ready to cover your marigold if you have one of those late frosts.

USDA Zone Info for Johnstown

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 Johnstown

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