When to Plant Leeks in Winthrop Harbor, IL

The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant leeks in Winthrop Harbor can be estimated 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.

Leeks are very cold tolerant which tells us that you can get them planted much earlier than other frost tender plants.

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 Winthrop Harbor 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. You probably don't want to wait any later than that or else your leeks may not have a chance to grow to maturity. Starting your leeks indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Winthrop Harbor. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Winthrop Harbor may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Winthrop Harbor you get surprised by a frost after April 15 be ready to cover your leeks in the event of one of those late frosts.

USDA Zone Info for Winthrop Harbor

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 Winthrop Harbor

You may be interested in your other planting guides for Winthrop Harbor.