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

You should be able to determine when it's a good idea to plant marigold by using the USDA zone info for Rosemount.

Planting Calendar for Marigold

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

It's probably not a good 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 Rosemount is May. However, you really should wait until June 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. 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

In Rosemount the average date of last frost happens on May 15. You should expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Rosemount is just an average the actual date of last frost changes from year to year. Half of the time in Rosemount you get surprised by a frost after May 15 so be sure to be ready to protect your marigold if you have one of those late frosts.

USDA Zone Info for Rosemount

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Rosemount

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