When to Plant Onion in USDA Zone 7b
Onions are a fundamental kitchen staple available in yellow, white, and red varieties. Choose long-day, short-day, or intermediate types based on your latitude.
In Zone 7b, the average last spring frost is around March 18 and the first fall frost is around November 8, giving you a growing season of approximately 235 days.
Onion Planting Timeline — Zone 7b
Where Is USDA Zone 7b?
The map below highlights the states that contain Zone 7b. Click any state to see the Onion planting schedule for that location.
Onion Planting Calendar — Zone 7b
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 11 | Feb 11 – Feb 25 |
| Transplant Outdoors | March 18 | Mar 18 – Apr 1 |
| Direct Sow | March 4 | Mar 4 – Mar 25 |
| Fall Sowing | August 30 | Aug 30 – Sep 13 |
| Harvest | June 17 | Jun 17 – Aug 5 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Transplant Outdoors Direct Sow |
| April | Transplant Outdoors |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Free Zone 7b Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 7b with start dates, transplant windows, and harvest times.
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
90–120 days
Soil pH
6 – 7
Zone Temperature Range
5°F to 10°F average annual minimum
Growing Season
235 days (Zone 7b average)
Planting Specifications
| Planting Depth | 1 inches |
| Plant Spacing | 6 inches apart |
| Row Spacing | 12 inches between rows |
Growing Tips for Zone 7b
Start seeds indoors 8-10 weeks before transplanting. Match day-length type to your latitude. Stop watering when tops begin to fall over and cure bulbs for 2-3 weeks before storage.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Saving Onion Seeds
Recommended for Your Garden
Start seeds indoors with reusable cell trays and humidity domes.
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
Keep your garden organized with durable, weather-resistant plant labels.
Related Plants
Onion in Other Zones
Onion by State
- Alabama
- Alaska
- Alberta
- Arizona
- Arkansas
- British Columbia
- California
- Colorado
- Connecticut
- Delaware
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Manitoba
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Brunswick
- New Hampshire
- New Jersey
- New Mexico
- New York
- Newfoundland and Labrador
- North Carolina
- North Dakota
- Northwest Territories
- Nova Scotia
- Nunavut
- Ohio
- Oklahoma
- Ontario
- Oregon
- Pennsylvania
- Prince Edward Island
- Quebec
- Rhode Island
- Saskatchewan
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
- Yukon
Frequently Asked Questions
When should I plant Onion in Zone 7b?
In Zone 7b, plan your Onion planting around the average last frost date of March 18. Start seeds indoors around February 11. Direct sow outdoors around March 4. Transplant seedlings around March 18.
Can Onion grow in Zone 7b?
Yes, Onion can grow well in Zone 7b, hardy in USDA zones 3a through 10b. Zone 7b has a growing season of approximately 235 days, which is sufficient for Onion (90-120 days to maturity).
When can I harvest Onion in Zone 7b?
In Zone 7b, expect to harvest Onion from June 17 – August 5. Onion takes 90-120 days from planting to harvest.
What is the last frost date for Zone 7b?
The average last spring frost in Zone 7b is around March 18, and the first fall frost is around November 8. This gives a growing season of approximately 235 days. These are 50% probability dates — actual frost dates vary year to year.
What should I plant next to Onion?
Good companion plants for Onion include Carrots, Lettuce, Beets, Cabbage. These companions can help with pest control, pollination, and nutrient sharing.
Plan Your Garden with Confidence
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