When to Plant Onion in Berkeley County, SC
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.
Berkeley County, South Carolina is in USDA Zone 8b. The average last spring frost is March 1 and the first fall frost is November 23, giving you a growing season of approximately 267 days.
At an elevation of 441 feet, Berkeley County receives approximately 52.8 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 93°F, providing good warmth for Onion during the growing season. Sandy soil warms quickly in spring — great for early planting — but Onion will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Onion root diseases.
Berkeley County Soil Profile
Soil Type
Sandy Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Onion Planting Timeline — Berkeley County, SC
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 25 | Jan 25 – Feb 8 |
| Transplant Outdoors | March 1 | Mar 1 – Mar 15 |
| Direct Sow | February 15 | Feb 15 – Mar 8 |
| Harvest | May 31 | May 31 – Jul 19 |
| Fall Sowing | September 14 | Sep 14 – Sep 28 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | Fall Sowing |
| 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 8b
📆 Growing Season
267 days in Berkeley County
Growing Tips for Berkeley 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 Berkeley County, SC?
Berkeley County is in Zone 8b with an average last frost of March 1. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Berkeley County, SC?
Berkeley County, South Carolina is in USDA Hardiness Zone 8b. The average last spring frost is March 1 and first fall frost is November 23.
Plan Your Garden with Confidence
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