Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of estimating when you can plant rosemary is to look at the USDA zone info for Des Plaines.

Planting Calendar for Rosemary

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

Rosemary can survive in cold weather which tells us that you can plant them a lot earlier in the year than more sensitive plants.

The earliest that you can plant rosemary in Des Plaines 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 little bit earlier by starting your rosemary indoors.

Last Frost Date

In Des Plaines the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -15°F.

Remember that USDA zone info for Des Plaines is just an average and the actual date of last frost is different every year. Half of the time in Des Plaines it frosts late in the year after April 15 so be sure to be ready to cover your rosemary in the event of one of those late frosts.

USDA Zone Info for Des Plaines

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 Des Plaines

You may be interested in your other planting guides for Des Plaines.