Growing Onions in Zone 9
When to plant and harvest onions in Zone 9— based on your zone's frost dates.
Zone 9 sits comfortably within onions' best range (Zones 3–9), so it grows well here on a standard schedule.
Onions planting calendar for Zone 9
These months are derived from Zone 9's frost dates — last frost around Late January – late February, first frost around Early December – early January.
Start indoors
December
Sow outdoors
September
Transplant
—
Harvest
May
Onions care at a glance
- Sunlight
- Full sun
- Water
- 1 inch per week; stop as tops fall
- Spacing
- 4 in apart
- Days to maturity
- 90–120 days
- Best zones
- 3–9 (choose day-length type for your latitude)
Growing onions in Zone 9: FAQs
Can you grow onions in Zone 9?＋
Zone 9 sits comfortably within onions' best range (Zones 3–9), so it grows well here on a standard schedule.
When should I plant onions in Zone 9?＋
In Zone 9, start seeds indoors around December. Zone 9's last spring frost is typically Late January – late February and its first fall frost around Early December – early January, which sets the planting window.
When to harvest onions in Zone 9?＋
Expect to harvest onions in Zone 9 around May, depending on the season and variety.
Full Onions guide →
Complete care, problems, companions, and harvest tips.
Zone 9 overview →
Frost dates, climate, and everything to grow here.
June in Zone 9 →
What to sow, transplant, and harvest this month.