🧅 When to Plant Leeks
Mild onion flavor; mound soil around stems as they grow to blanch and extend edible shank
📅 Planting Calendar by USDA Zone
Leeks is a cool-season crop — plant it around your last spring frost, and you can often start it earlier indoors or sow again for a fall harvest. Find the exact start-indoors, transplant, and direct-sow dates for your USDA zone in the table below.
Select your zone to highlight your dates. All dates are calculated from each zone's average frost dates — see how we calculate them.
| Zone | Last Frost | Start Indoors | Transplant | Direct Sow |
|---|---|---|---|---|
| Zone 2A | May 30 | Mar 21 | May 2 | — |
| Zone 3B | May 15 | Mar 6 | Apr 17 | — |
| Zone 4A | May 8 | Feb 27 | Apr 10 | — |
| Zone 4B | May 1 | Feb 20 | Apr 3 | — |
| Zone 5A | Apr 25 | Feb 14 | Mar 28 | — |
| Zone 5B | Apr 18 | Feb 7 | Mar 21 | — |
| Zone 6A | Apr 21 | Feb 10 | Mar 24 | — |
| Zone 6B | Apr 10 | Jan 30 | Mar 13 | — |
| Zone 7A | Apr 5 | Jan 25 | Mar 8 | — |
| Zone 7B | Mar 28 | Jan 17 | Feb 28 | — |
| Zone 8A | Mar 20 | Jan 9 | Feb 20 | — |
| Zone 8B | Mar 12 | Jan 1 | Feb 12 | — |
| Zone 9A | Feb 28 | Dec 20 | Jan 31 | — |
| Zone 9B | Feb 15 | Dec 7 | Jan 18 | — |
| Zone 10A | Feb 1 | Nov 23 | Jan 4 | — |
| Zone 10B | Jan 15 | Nov 6 | Dec 18 | — |
| Zone 11A | Jan 1 | Oct 23 | Dec 4 | — |
Leeks are the mildest, most cold-hardy member of the allium family. They can overwinter in the ground in zones 5+ and provide harvests well into winter when other crops have finished.
Top Growing Tips
- Start indoors 10-12 weeks before last frost — one of the earliest starts needed
- Transplant into narrow holes 6 inches deep; drop seedling in and let soil fill naturally
- Mound soil around the shank as plants grow to blanch and lengthen the white portion
- Tolerates light freeze and can be mulched to extend harvest into December
- Harvest after first frost for the sweetest, most complex flavor
Companion Planting
Good companions: carrots, celery, onions, brassicas
Avoid planting near: legumes (beans, peas)
Harvest Timeline
100-120 days from transplant; harvest when shank is 1 inch or more in diameter
Growing leeks in your region?
These dates come from your zone's frost windows. For the full month-by-month plan — succession sowing, variety picks, and timing tuned to your climate, not just your zone — our regional vegetable-gardening guides cover your area start to finish.
Find your regional growing guide