Planting timing · Cool-season
When to plant leeks
Plant leeks on the cited sheets — not on a national calendar month. Regional dates stay source-specific.
Growing guidance is general information. Timing, spacing, and care depend on cultivar, weather, soil, and local conditions. Check the sources and adjust the plan for your garden.
Spacing lives on the leeks hub. Timing stays on the cited sheets.
Types and spacing live on growing leeks.
What the sources say — at a glance
One source per card. Facts are not averaged.
Clemson HGIC 1314 (South Carolina)
Late summer or early fall for winter harvest. Mature below 75 °F. Timing on their sheet — not a national plant date.
Details and limits (2)
Timing
Clemson HGIC 1314 (South Carolina): leeks are planted in late summer or early fall for winter harvest. Leeks mature best during temperatures averaging below 75 °F. Timing on their sheet — not a national plant date.
Limit
South Carolina HGIC 1314. Late-summer/early-fall timing stays Clemson. Not a ZIP calendar.
Maryland Extension (Maryland)
Indoor for early spring transplants, or later summer for fall. Several weeks prior to last frost. Maryland timing — not a national plant date.
Details and limits (2)
Timing
Maryland Extension (Maryland): start seeds indoors for early spring transplants or later in the summer for a fall crop. Leeks can be planted several weeks prior to the last frost date. Maryland timing — not a national plant date. Maryland’s attributed frost-date wording — not a planting-safety promise.
Limit
Maryland leeks garden page. Frost-date wording stays Maryland. Not a ZIP calendar.
UMN Extension (Minnesota)
Indoor start. Transplant in early spring. Minnesota timing — not a national plant date.
Details and limits (2)
Timing
UMN Extension (Minnesota): start seeds indoors and transplant in early spring. Minnesota timing — not a national plant date.
Limit
Minnesota leeks page. Early-spring transplant stays Minnesota. Not a ZIP calendar.
Sources differ
Make it yours
Save the bed in the Field Book so next season is not a guess.
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No supplier on this page
When a partner is listed, it will be outbound and disclosed. Nothing to buy here. Fertilizer, soils, and pesticides stay off this slot.
When do you plant leeks?
Compare timing on the cited sheets. Clemson HGIC 1314 (South Carolina): late summer or early fall for winter harvest. Maryland: indoor starts for early spring transplants, or later in the summer for a fall crop. Minnesota: indoor start, transplant in early spring.
Do the sheets agree on a window?
No. Clemson names late summer or early fall. Maryland names early spring transplants or a later-summer fall crop. Minnesota names early spring. Three cards — not averaged.
What to record in the Field Book
Save the bed with the crop and the date. You may add a photo and notes. Compare entries you have recorded with each other — not with a diagnosis from this page. If you want an identification, bring the record to local Extension.
How we know — methodology. Ranges and assertions are cited per source, not blended.