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.

The USDA zone info for Fergus Falls should be reviewed to figure out when it's the best time to plant helianthemum.

Planting Calendar for Helianthemum

Frost tolerance for helianthemum:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Helianthemum are one of those plants that can tolerate a little bit of cold weather which means that you can get them planted earlier than other frost tender plants.

The earliest that you can plant helianthemum in Fergus Falls is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant helianthemum and expect a good harvest is probably August. If you wait any later than that and your helianthemum may not have a chance to grow to maturity. If you are starting your helianthemum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Fergus Falls. You can expect an average low temperature of -30°F in the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Fergus Falls and it changes from year to year. Half of the time in Fergus Falls last frost occurs after May 15 so be sure to be ready to protect your helianthemum in the event of a surprise late frost.

USDA Zone Info for Fergus Falls

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Fergus Falls

You may be interested in your other planting guides for Fergus Falls.