Before planting it is a good idea to find your USDA Zone info to estimate 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.

In Princeton you can determine when to plant common hollyhock by using 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 well in mild cold which means that you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant common hollyhock in Princeton 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. 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 little bit earlier.

Last Frost Date

In Princeton the average date of last frost happens on March 15. In the coldest months of winter you can expect an average low temperature of 10°F.

Since the USDA zone info for Princeton may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Princeton there is a last frost after March 15 be ready to protect your common hollyhock if you have a late frost.

USDA Zone Info for Princeton

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

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

Plants to Grow in Princeton

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