When to Plant Rosemary in Chatham, IL

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.

In Chatham you can determine when it's possible to plant rosemary by reviewing 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.

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

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant rosemary
Possibly ok, but a risky time to plant rosemary
Probably not a good time to plant rosemary

The earliest that you can plant rosemary in Chatham 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 fully mature. You can get started a couple of weeks earlier by starting your rosemary indoors.

Last Frost Date

The average date of last frost is April 15 in Chatham. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Chatham is just an average the actual date of last frost changes from year to year. Since half of the time in Chatham last frost occurs after April 15 be ready to cover your rosemary if you have one of those late frosts.

USDA Zone Info for Chatham

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 Chatham

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