When to Plant Rosemary in Crystal Lake, IL

One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Crystal Lake you can determine when it's a good idea to plant rosemary 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.

Rosemary are very cold tolerant which means that you can get them planted much earlier than plants that are more sensitive to the cold.

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 Crystal Lake 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. Starting your rosemary indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Crystal Lake is not always accurate the actual date of last frost will vary from year to year. Half of the time in Crystal Lake you get surprised by a frost after April 15 so make sure that you are prepared to cover your rosemary if you have one of those late frosts.

USDA Zone Info for Crystal Lake

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 Crystal Lake

You may be interested in your other planting guides for Crystal Lake.