When to Plant Leeks in Illinois
Illinois spans USDA hardiness 5a to 7a (zones 5a to 7a on this page). Plant leeks by your local frost date, not the calendar — pick your zone below for exact start-indoors, transplant, and harvest dates.
Jump to: Zone 5a · Zone 5b · Zone 6a · Zone 6b · Zone 7a
Leeks planting calendar for Illinois, Zone 5a
Average last spring frost
May 5
Average first fall frost
October 1
Direct sow
Nov 4
Projected first harvest
Jul 2
Most leeks mature in about 130 to 240 days depending on the variety. Full zone 5 guide (both 5a and 5b) →
Leeks planting calendar for Illinois, Zone 5b
Average last spring frost
April 30
Average first fall frost
October 5
Direct sow
Oct 30
Projected first harvest
Jun 27
Most leeks mature in about 130 to 240 days depending on the variety. Full zone 5 guide (both 5a and 5b) →
Leeks planting calendar for Illinois, Zone 6a
Average last spring frost
April 25
Average first fall frost
October 10
Direct sow
Oct 25
Projected first harvest
Jun 22
Most leeks mature in about 130 to 240 days depending on the variety. Full zone 6 guide (both 6a and 6b) →
Leeks planting calendar for Illinois, Zone 6b
Average last spring frost
April 20
Average first fall frost
October 15
Direct sow
Oct 20
Projected first harvest
Jun 17
Most leeks mature in about 130 to 240 days depending on the variety. Full zone 6 guide (both 6a and 6b) →
Leeks planting calendar for Illinois, Zone 7a
Average last spring frost
April 15
Average first fall frost
October 20
Direct sow
Oct 15
Projected first harvest
Jun 12
Most leeks mature in about 130 to 240 days depending on the variety. Full zone 7 guide (both 7a and 7b) →
Not sure which half-zone you're in? Set your ZIP in HomeSown for dates tuned to your exact location.
Varieties to grow
2 varieties of leeks in the HomeSown library. Tap any for its full grow guide.
Common problems with leeks
What to watch for, with identification and treatment for each
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