When to plant Onion in Barton County, KS
In Barton County, plant Onion in spring between April 6 and April 27, once soil temps hold above 50°F. Barton County's last frost averages April 20, so time plantings around the expected last-frost window for best survival. For a fall crop, sow between August 7 and August 21 — roughly 90–120 days before the first frost on October 16.
When to Plant Onion in Barton County, KS
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.
Barton County, Kansas is in USDA Zone 6b. The average last spring frost is April 20 and the first fall frost is October 16, giving you a growing season of approximately 179 days.
At an elevation of 638 feet, Barton County receives approximately 25.9 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Onion during the growing season.
Barton County Soil Profile
Soil Type
Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Onion Planting Timeline — Barton County, KS
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 16 | Mar 16 – Mar 30 |
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Direct Sow | April 6 | Apr 6 – Apr 27 |
| Harvest | July 20 | Jul 20 – Sep 7 |
| Fall Sowing | August 7 | Aug 7 – Aug 21 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 6b
📆 Growing Season
179 days in Barton County
Growing Tips for Barton County
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
Check more plant combinations with our Companion Planting Checker →
Onion in Other Locations
Frequently Asked Questions
When should I plant Onion in Barton County, KS?
Barton County is in Zone 6b with an average last frost of April 20. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Barton County, KS?
Barton County, Kansas is in USDA Hardiness Zone 6b. The average last spring frost is April 20 and first fall frost is October 16.
When should I plant Onion in Barton County, KS?
In Barton County, KS, plant Onion after the last frost (around April 20) and before the first frost (around October 16). Best results when soil holds above 50°F.
What growing zone is Barton County, KS for Onion?
Barton County sits in USDA Zone 6b. Onion grows reliably in zones 3a through 10b, so it's a good fit here.
Can Onion grow in Barton County's climate?
Yes — Onion grows well in Barton County's temperate climate. Barton County averages a 179-day frost-free season, with last frost around April 20 and first frost around October 16.
Your Barton County Garden Planner — Free
A 22-page printable planner built for Barton County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.