One of the best tools that you have as gardeners to help us determine 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 earliest that you can plant common hollyhock in Trenton can be estimated 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.

Since common hollyhock do well in moderate cold you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant common hollyhock in Trenton 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 really do well. Starting your common hollyhock indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Trenton the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 0°F.

Just be sure to remember that USDA zone info for Trenton may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Trenton last frost occurs after April 15 be ready to cover your common hollyhock if you have a late frost.

USDA Zone Info for Trenton

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 Trenton

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