📍 Combs, AR · Zone 7b · Last frost Sunday, April 5, 2026
✏️ ChangeWhen to Plant Onion in Combs, Arkansas (72721)
Location
Combs, Arkansas
ZIP Code
72721
USDA Zone
7b
Last Frost
Sunday, April 5, 2026
📅 Your 2026 Planting Dates
Start Seeds Indoors
Sunday, February 8, 2026
Transplant Outdoors
Sunday, April 19, 2026
Based on last frost Sunday, April 5, 2026 · Zone 7b
Pro tip: Start Onion seeds indoors 8 weeks before your last frost date, then transplant outdoors around Sunday, April 19, 2026.
🌿 Plant Details
☀️ Growing Requirements
☀️
Sun
Full Sun (6+ hours)
💧
Water
Moderate
↔️
Spacing
4" apart
🌱
Planting Depth
0.5" deep
Seeds typically germinate in 7-10 days
Ready to Plant Onion in Combs?
Get your seeds now so they're ready by Sunday, February 8, 2026.
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🤝 Good Companions
⚠️ Avoid Planting Near
Full Companion Planting Guide for Onion
See which plants help Onion thrive, which to keep away, and raised bed layout tips →
🛠️ Supplies You'll Need
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Common Onion Varieties
Popular cultivars to look for at your local nursery or seed supplier.
Yellow Sweet Spanish
Large, mild onion with golden skin; the most widely grown long-day onion in North America.
Red Burgundy
Short-day red onion with mild, sweet flavor; excellent for fresh eating and salads.
Candy
High-yielding intermediate-day onion with sweet, mild flavor; stores well.
Walla Walla Sweet
Famous Pacific Northwest sweet onion with very low pungency and high sugar content.
Cipollini
Small, flat Italian onion with intense sweetness; prized for roasting and caramelizing.
Common Onion Problems
What to watch for — and how to fix it before it spreads.
Pests
Tiny insects rasp leaf surfaces leaving silver streaking; transmit iris yellow spot virus.
Apply spinosad or insecticidal soap; use reflective mulch; avoid planting near grass.
Fly larvae tunnel into bulbs causing plants to collapse; worst in cool, wet springs.
Use row covers; rotate crops far from previous onion beds; till soil to expose pupae to birds.
Soil-dwelling larvae bore small tunnels into developing bulbs.
Till deeply before planting; plant buckwheat as a trap crop; use beneficial nematodes.
Diseases
Gray mold at the neck of stored bulbs; spreads through the bulb in storage.
Cure bulbs thoroughly (2–3 weeks in warm, dry, airy space) before storage.
Water-soaked white lesions that turn purple; leaves collapse and dry in wet weather.
Apply copper fungicide; avoid overhead watering; plant in well-draining soil.
Pink-red discoloration at the base of the bulb; common in hot soils.
Rotate crops; improve drainage; plant resistant varieties; avoid injuring bulbs at planting.
Common Mistakes
Short-day onions won't form bulbs in northern regions; long-day varieties stay tiny in the South.
Choose long-day varieties (14+ hours) for north of 35°N, short-day for south of 35°N, intermediate for in between.
Deep-planted sets or transplants have energy diverted away from bulb development.
Plant sets or transplants so the top of the bulb/root mass is just at or slightly below soil surface.
🌾 Seed Saving Guide
🟡 ModerateWhen to Harvest Seed
Allow seed heads to form in year 2 (onions are biennial). Harvest when most seeds are black and visible.
Processing
Cut seed heads into bags, dry 1 week, shake to release seeds.
Seed Viability
Up to 1 year when stored cool, dark, and dry.
Pro Tip
Onion seed is very short-lived — use within 1 year. Cross-pollinates with other onion varieties via insects.
Raised Bed Planting Guides
A 4×8 bed fits 9 per sq ft of Onion. See plant counts, spacing grids, and companion pairings for every bed size →
Frequently Asked Questions
When should I plant Onion in Combs, Arkansas? +
In Combs (Zone 7b), start Onion seeds indoors around Sunday, February 8, 2026 and transplant outdoors around Sunday, April 19, 2026.
What is the last frost date for Combs, Arkansas? +
The average last spring frost date for Combs, Arkansas (ZIP 72721) is around Sunday, April 5, 2026. This is based on NOAA climate normals for USDA Zone 7b.
How long does Onion take to grow? +
Onion typically matures in about 100 days from transplanting. In Combs, that means you can expect harvest around Sunday, April 19, 2026 plus 100 days.
Should I start Onion indoors or direct sow in Arkansas? +
Onion should be started indoors 8 weeks before your last frost date. In Combs, that means starting around Sunday, February 8, 2026.
Other Plants for Combs
Growing Onion in Zone 7b
Onion (Allium cepa) is a popular garden vegetable. In Combs, Arkansas, which is in USDA Hardiness Zone 7b, you should start seeds indoors around Sunday, February 8, 2026.
Your average last frost date is Sunday, April 5, 2026. Plan to transplant your Onion seedlings outdoors around Sunday, April 19, 2026, about 2 weeks after your last frost date.