When to Plant Rosemary in Sullivan, IL

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 first opportunity to plant rosemary in Sullivan should be estimated 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.

You can plant rosemary quite a bit earlier in the year because they are very cold tolerant.

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 Sullivan 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. Starting your rosemary indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Sullivan may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Sullivan you get surprised by a frost after April 15 be ready to cover your rosemary if you have a late frost.

USDA Zone Info for Sullivan

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 Sullivan

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