When to Plant Leeks in Wilmette, 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.

The USDA zone info for Wilmette can be reffered to in order to figure out when you can plant leeks.


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 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 leeks
Possibly ok, but a risky time to plant leeks
Probably not a good time to plant leeks

The earliest that you can plant leeks in Wilmette 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 grow to maturity. If you are starting your leeks indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Wilmette the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

It's important to remember that USDA zone info for Wilmette is an average and the actual date of last frost is different every year. Since half of the time in Wilmette you get surprised by a frost after April 15 be ready to cover your leeks in the event of a surprise late frost.

USDA Zone Info for Wilmette

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 Wilmette

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