The USDA Zone info is a great tool for gardeners to help us estimate your gardening 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 estimate when it's the best time to plant common hollyhock by checking out the USDA zone info for Collegeville.

Planting Calendar for Common hollyhock

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

Since common hollyhock are one of those plants that can tolerate a little bit of cold weather you can plant them a little bit earlier in the year than other plants that might not handle the cold.

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

Last Frost Date

On average the last frost is on April 15 in Collegeville. You should expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Collegeville is an average the actual date of last frost will vary from year to year. Half of the time in Collegeville last frost occurs after April 15 so make sure that you are prepared to protect your common hollyhock if you have one of those late frosts.

USDA Zone Info for Collegeville

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Collegeville

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