One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In River Falls you can figure out when it's possible to plant rudbeckia by checking out the USDA zone info.

Planting Calendar for Rudbeckia

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

Since rudbeckia do well in moderate cold you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant rudbeckia in River 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 rudbeckia and expect a good harvest is probably August. Any later than that and your rudbeckia may not have a chance to fully mature. Starting your rudbeckia indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is May 15 in River Falls. In the coldest months of winter you should expect an average low temperature of -25°F.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for River Falls and it is different every year. Since half of the time in River Falls you get a frost after May 15 be ready to cover your rudbeckia if you have a 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.