Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Downers Grove you can determine when it's the best time to plant thyme by referring to the USDA zone info.

Planting Calendar for Thyme

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

Thyme do well in cold which tells us that you can get them planted much earlier than more sensitive plants.

The earliest that you can plant thyme in Downers Grove 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 thyme and expect a good harvest is probably September. Any later than that and your thyme may not have a chance to fully mature. Starting your thyme indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Downers Grove 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 Downers Grove is an average the actual date of last frost will vary from year to year. Since half of the time in Downers Grove it frosts late in the year after April 15 be ready to cover your thyme in the event of one of those late frosts.

USDA Zone Info for Downers Grove

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 Downers Grove

You may be interested in your other planting guides for Downers Grove.