When to Plant Onion in USDA Zone 7a
Top priorities for Zone 7a gardeners in May
Each item below is timed to Zone 7a's frost dates and soil temperatures. Skip nothing, stress about nothing.
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Start onion indoors
Your window is short. These crops want several weeks of indoor growth before they go outside.
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 7a, the average last spring frost is around March 25 and the first fall frost is around November 1, giving you a growing season of approximately 221 days.
Onion Planting Timeline — Zone 7a
Where Is USDA Zone 7a?
The map below highlights the states that contain Zone 7a. Click any state to see the Onion planting schedule for that location.
Onion Planting Calendar — Zone 7a
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 18 | Feb 18 – Mar 4 |
| Transplant Outdoors | March 25 | Mar 25 – Apr 8 |
| Direct Sow | March 11 | Mar 11 – Apr 1 |
| Harvest | June 24 | Jun 24 – Aug 12 |
| Fall Sowing | August 23 | Aug 23 – Sep 6 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Free Zone 7a Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 7a 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
°F to °F average annual minimum
Growing Season
221 days (Zone average)
Planting Specifications
| Planting Depth | 1 inches |
| Plant Spacing | 6 inches apart |
| Row Spacing | 12 inches between rows |
Growing Tips for Onion in Zone
Zone has a short growing season (~221 days). Start Onion indoors early and use season-extension techniques like row covers and cold frames.
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
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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
- 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 Onion in Zone 7a?
In Zone 7a, plan your Onion planting around the average last frost date of March 25. Start seeds indoors around February 18. Direct sow outdoors around March 11. Transplant seedlings around March 25.
Can Onion grow in Zone 7a?
Yes, Onion can grow well in Zone 7a, hardy in USDA zones 3a through 10b. Zone 7a has a growing season of approximately 221 days, which is sufficient for Onion (90-120 days to maturity).
When can I harvest Onion in Zone 7a?
In Zone 7a, expect to harvest Onion from June 24 – August 12. Onion takes 90-120 days from planting to harvest.
What is the last frost date for Zone 7a?
The average last spring frost in Zone 7a is around March 25, and the first fall frost is around November 1. This gives a growing season of approximately 221 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.
Your Free Printable Garden Planner
A 24-page printable planner tailored to your zone. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.