One of the best tools that you have as gardeners to help us estimate 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.

The USDA zone info for Niles can be reffered to in order to determine when it's the best time to plant common hollyhock.

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 can survive in mild cold which tells us that you can plant them a little earlier in the year than other frost tender plants.

The earliest that you can plant common hollyhock in Niles 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 common hollyhock and expect a good harvest is probably September. You probably don't want to wait any later than that or else your common hollyhock may not have a chance to really do well. 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

On average the last frost has passed is on April 15 in Niles. In the coldest months of winter you should expect an average low temperature of -15°F.

Keep in mind that USDA zone info for Niles is not always accurate and the actual date of last frost is different every year. Since half of the time in Niles you get surprised by a frost after April 15 be ready to protect your common hollyhock if you have a surprise late frost.

USDA Zone Info for Niles

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Niles

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