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 should be able to determine when you can plant hollyhocks by using the USDA zone info for Green Bay.

Planting Calendar for Hollyhocks

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

Hollyhocks do well in moderate cold which tells us that you can plant them earlier than other plants that might not handle the cold.

The earliest that you can plant hollyhocks in Green Bay is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant hollyhocks and expect a good harvest is probably September. Any later than that and your hollyhocks may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your hollyhocks indoors.

Last Frost Date

In Green Bay the average date of last frost happens on April 15. You should expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Green Bay may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Green Bay last frost occurs after April 15 be ready to protect your hollyhocks in the event of a late frost.

USDA Zone Info for Green Bay

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Green Bay

You may be interested in your other planting guides for Green Bay.