✓
Growing Walla Walla in Zone 12b
Allium cepa
✓ Well Suited for Zone 12b
Score: 100/100
🌡️ USDA Hardiness Zone 12b
Tropical
USDA 2023 Verified
Growing Season
365-365 days
Winter Minimum
55°F to 60°F
(12.8°C to 15.6°C)
AHS Heat Zone 12-12
More than 210 heat days per year • Extreme heat stress
Typical regions: Hawaii coastal, Puerto Rico coastal, US Virgin Islands
📊 Data Source:
USDA Plant Hardiness Zone Map 2023 • Last verified: 1/22/2026
✓ Zone Compatibility Analysis
high confidenceExcellent match: 105 days to maturity with 260 days buffer in 365-day season.
Recommendation: Direct sowing and transplanting both viable. Excellent fit for this zone.
💾 Suitability computed by Solara Agricultural Intelligence Platform
📅 Zone 12b Planting Calendar for Walla Walla
🌱 Start Seeds Indoors
March 12
✓ Database-computed optimal date
🪴 Transplant Outdoors
April 30
✓ Database-computed optimal date
🌾 Direct Sow (Alternative)
2 weeks after last frost
For warm-season crops
🥕 Expected Harvest
August 13
💡 Zone 12b Growing Tips
- • Growing season: 365-365 frost-free days
- • Excellent match for this zone - both direct sowing and transplanting work well
- • Monitor soil temperature before transplanting (minimum 55-60°F for most crops)
⚠️ Zone 12b Challenges
⚠️Tropical storms
⚠️Salt spray
⚠️High humidity
✅ Best Plants for Zone 12b
✓All tropical fruits
✓Coconuts
✓Tropical ornamentals
❄️ Winter in Zone 12b
Frost-free year-round. Minimum temperatures 55°F-60°F.
☀️ Summer in Zone 12b
Warm, humid year-round. Continuous growing season.
🔥 Heat Management for AHS Zone 12-12
This zone experiences more than 210 heat days per year with extreme heat stress.
🌡️Tropical varieties only
🌡️Constant irrigation
🌡️Shade essential
🌡️Heat-adapted cultivars required
Source: American Horticultural Society
📊 Walla Walla Quick Facts
Days to Maturity
90-120
Difficulty
intermediate
Season
summer
Type
OP
📍 View Walla Walla Guide for Other Zones
🌱 Other Onion Varieties for Zone 12b
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