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

You can determine when to plant common hollyhock in River Falls by referring to the USDA zone info.

Planting Calendar for Common hollyhock

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

Common hollyhock do ok in a little bit of cold which means that you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant common hollyhock 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 common hollyhock and expect a good harvest is probably August. If you wait any later than that and your common hollyhock may not have a chance to grow to maturity. If you are starting your common hollyhock indoors then you might be able to get away with starting them a couple of weeks earlier.

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.

It's important to remember that USDA zone info for River Falls is just an average and the actual date of last frost is different every year. Half of the time in River Falls you get surprised by a frost after May 15 so make sure that you are ready to cover your common hollyhock in the event of 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.