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.

By referring to the USDA zone info for Carol Stream it's possible to figure out when it's a good idea to plant leeks.

Planting Calendar for Leeks

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

Since leeks are one of those plants that can tolerate quite a bit of cold weather you can plant them quite a bit earlier in the year than other frost tender plants.

The earliest that you can plant leeks in Carol Stream 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 leeks and expect a good harvest is probably September. Any later than that and your leeks may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your leeks indoors.

Last Frost Date

The average date of last frost is April 15 in Carol Stream. In the coldest months of winter you can expect an average low temperature of -15°F.

Always keep in mind that USDA zone info for Carol Stream is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Carol Stream there is a last frost after April 15 so always be ready to cover your leeks in the event of one of those late frosts.

USDA Zone Info for Carol Stream

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 Carol Stream

You may be interested in your other planting guides for Carol Stream.