Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to determine when it's the best time to plant black eyed susans by looking at the USDA zone info for River Falls.

Planting Calendar for Black Eyed Susans

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

Black Eyed Susans require warm weather which means that it's necessary to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant black eyed susans in River Falls 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 black eyed susans and expect a good harvest is probably August. If you wait any later than that and your black eyed susans may not have a chance to fully mature. You can get started a little bit earlier by starting your black eyed susans indoors.

Last Frost Date

In River Falls the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for River Falls and it changes from year to year. Since half of the time in River Falls it frosts late in the year after May 15 be ready to cover your black eyed susans in the event of a surprise late frost.

USDA Zone Info for River Falls

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 River Falls

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