The USDA Zone info is a great tool for gardeners to help us estimate 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 Hartford can be read 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 tells us that you can get them planted much earlier than other frost tender plants.

The earliest that you can plant rosemary in Hartford 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. If you wait any later than that and your rosemary may not have a chance to really do well. If you are starting your rosemary indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Hartford the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Hartford and it is different every year. Half of the time in Hartford you get surprised by a frost after April 15 so just be sure to be ready to protect your rosemary if you have a surprise late frost.

USDA Zone Info for Hartford

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Hartford

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