When to Plant Rosemary in Round Lake, IL

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

By checking out the USDA zone info for Round Lake it's possible to estimate when to plant rosemary.


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 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 Round 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 fully mature. If you are starting your rosemary indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Round Lake 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 Round Lake is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Round Lake there is a last frost after April 15 so make sure that you are prepared to protect your rosemary if you have one of those late frosts.

USDA Zone Info for Round 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 Round Lake

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