When to Plant Rosemary in Sandwich, IL

One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Sandwich you can estimate when it's the best time to plant rosemary by reviewing 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 do well in cold 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 Sandwich 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 grow to maturity. Starting your rosemary indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Sandwich 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 the actual date of last frost is just an average because it is based on the USDA zone info for Sandwich and it can change quite a bit from year to year. Half of the time in Sandwich last frost occurs after April 15 so be sure to be ready to cover your rosemary if you have a surprise late frost.

USDA Zone Info for Sandwich

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 Sandwich

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