One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when to plant leeks in North Chicago by referring to the USDA zone info.

Planting Calendar for Leeks

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

You can plant leeks a lot earlier in the year because they are very cold tolerant.

The earliest that you can plant leeks in North Chicago 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. If you wait any later than that and your leeks may not have a chance to really do well. If you are starting your leeks indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost is on April 15 in North Chicago. It might get as low as -15°F during the coldest months of winter.

Keep in mind that USDA zone info for North Chicago may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in North Chicago last frost occurs after April 15 be ready to cover your leeks in the event of a surprise late frost.

USDA Zone Info for North Chicago

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 North Chicago

You may be interested in your other planting guides for North Chicago.