One of the best tools that you have as gardeners to help us figure out 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.

In Oak Park you can estimate when it's the best time to plant rosemary by using the USDA zone info.

Planting Calendar for Rosemary

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

Rosemary do well in cold which tells us that you can plant them a quite a bit earlier than other frost tender plants.

The earliest that you can plant rosemary in Oak Park 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. You probably don't want to wait any later than that or else your rosemary may not have a chance to really do well. Starting your rosemary indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Oak Park the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Oak Park is just an average and the actual date of last frost is different every year. Since half of the time in Oak Park last frost occurs after April 15 be ready to cover your rosemary in the event of one of those late frosts.

USDA Zone Info for Oak Park

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°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 -5°F.

Plants to Grow in Oak Park

You may be interested in your other planting guides for Oak Park.