The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. 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 Trenton should be reffered to in order to estimate when it's possible to plant rosemary.

Planting Calendar for Rosemary

Frost tolerance for rosemary:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Rosemary are very cold tolerant which means that you can get them planted much earlier than other plants that might not handle the cold.

The earliest that you can plant rosemary 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 rosemary and expect a good harvest is probably September. Any later than that and your rosemary may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your rosemary indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Trenton. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Trenton is just an average the actual date of last frost will vary from year to year. Since half of the time in Trenton you get surprised by a frost after April 15 be ready to protect your rosemary in the event of one of those late frosts.

USDA Zone Info for Trenton

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 Trenton

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