Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Trenton you can determine when it's possible to plant hollyhocks by referring to the USDA zone info.

Planting Calendar for Hollyhocks

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

You can plant hollyhocks a little bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant hollyhocks 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 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

On average the last frost has passed is on April 15 in Trenton. In the coldest months of winter you can expect an average low temperature of -5°F.

Since the USDA zone info for Trenton is not always accurate the actual date of last frost can change quite a bit from year to year. Since half of the time in Trenton you get surprised by a frost after April 15 be ready to cover your hollyhocks in the event of a late frost.

USDA Zone Info for Trenton

Here is the info for USDA Zone 6b.

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

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

Plants to Grow in Trenton

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