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 chance to plant rosemary in Bourbonnais should be estimated by referring to 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 do well in cold.

The earliest that you can plant rosemary in Bourbonnais 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 really do well. You can get started a few weeks earlier by starting your rosemary indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Bourbonnais. In the coldest months of winter you should expect an average low temperature of -15°F.

Keep in mind that USDA zone info for Bourbonnais is not always accurate and the actual date of last frost is different every year. Half of the time in Bourbonnais there is a last frost after April 15 so be sure to be ready to cover your rosemary if you have a surprise late frost.

USDA Zone Info for Bourbonnais

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 Bourbonnais

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