When to Plant Leeks in USDA Zone 10b
Leeks are a mild, sweet allium that produces long white shanks. They are more refined than onions and are a key ingredient in soups, stews, and gratins.
In Zone 10b, the average last spring frost is around January 1 and the first fall frost is around December 31, giving you a growing season of approximately 364 days.
Leeks Planting Timeline — Zone 10b
Where Is USDA Zone 10b?
The map below highlights the states that contain Zone 10b. Click any state to see the Leeks planting schedule for that location.
Leeks Planting Calendar — Zone 10b
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | December 4 | Dec 4 – Dec 18 |
| Transplant Outdoors | January 1 | Jan 1 – Jan 15 |
| Direct Sow | December 11 | Dec 11 – Jan 1 |
| Harvest | April 2 | Apr 2 – Jun 18 |
| Fall Sowing | November 5 | Nov 5 – Nov 19 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Transplant Outdoors Direct Sow |
| February | — |
| March | — |
| April | Harvest |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | — |
| October | — |
| November | Fall Sowing |
| December | Start Indoors Direct Sow |
Free Zone 10b Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 10b with start dates, transplant windows, and harvest times.
Growing Conditions
Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
Days to Maturity
90–150 days
Soil pH
6 – 7
Zone Temperature Range
35°F to 40°F average annual minimum
Growing Season
364 days (Zone 10b average)
Planting Specifications
| Planting Depth | 1 inches |
| Plant Spacing | 15 inches apart |
| Row Spacing | 24 inches between rows |
Growing Tips for Leeks in Zone 10b
Zone 10b offers a long growing season (~364 days). You can plant Leeks earlier and may get multiple harvests.
Start seeds indoors 10-12 weeks before last frost. Transplant into trenches and hill soil around stems as they grow to increase the white portion. Harvest as needed.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Saving Leeks Seeds
Recommended for Your Garden
Reduce heat stress and sun scorch in hot climates with UV-stabilized shade cloth.
Start seeds indoors with reusable cell trays and humidity domes.
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
Related Plants
Leeks in Other Zones
Leeks by State
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
Frequently Asked Questions
When should I plant Leeks in Zone 10b?
In Zone 10b, plan your Leeks planting around the average last frost date of January 1. Start seeds indoors around December 4. Direct sow outdoors around December 11. Transplant seedlings around January 1.
Can Leeks grow in Zone 10b?
Yes, Leeks can grow well in Zone 10b, hardy in USDA zones 3a through 10b. Zone 10b has a growing season of approximately 364 days, which is sufficient for Leeks (90-150 days to maturity).
When can I harvest Leeks in Zone 10b?
In Zone 10b, expect to harvest Leeks from April 2 – June 18. Leeks takes 90-150 days from planting to harvest.
What is the last frost date for Zone 10b?
The average last spring frost in Zone 10b is around January 1, and the first fall frost is around December 31. This gives a growing season of approximately 364 days. These are 50% probability dates — actual frost dates vary year to year.
What should I plant next to Leeks?
Good companion plants for Leeks include Carrots, Celery, Lettuce. These companions can help with pest control, pollination, and nutrient sharing.
Plan Your Garden with Confidence
Get our free Garden Planner — organize your planting dates for Zone 10b, track your crops, and plan your garden season from seed to harvest.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.