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 can determine when it's a good idea to plant common hollyhock in Potsdam 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 are moderately cold tolerant which tells us that you can get them planted earlier than other frost tender plants.

The earliest that you can plant common hollyhock in Potsdam 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 fully mature. Starting your common hollyhock indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Potsdam may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Potsdam there is a last frost after May 15 be ready to protect your common hollyhock in the event of a late frost.

USDA Zone Info for Potsdam

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 Potsdam

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