When to Plant Leeks in Lombard, IL

One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's a good idea to figure out when to plant leeks by checking out the USDA zone info for Lombard.


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 means that you can start planting them much earlier than more sensitive 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 Lombard 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 really do well. You can get started a couple of weeks earlier by starting your leeks indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Lombard. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Lombard may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Lombard you get surprised by a frost after April 15 be ready to cover your leeks if you have one of those late frosts.

USDA Zone Info for Lombard

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 Lombard

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