How to Grow Oklahoma Red Onion
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Oklahoma Red Onion
Allium cepa 'Oklahoma Red'
vegetableOklahoma Red is a red onion variety known for its deep burgundy-red skin and mild, sweet flavor. It's a long-day variety that produces medium to large bulbs and stores exceptionally well. This heirloom cultivar is popular for fresh eating, grilling, and storage due to its excellent keeping qualities.
When should you plant Oklahoma Red Onion in your zone?
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Example Oklahoma Red Onion timeline · Pittsburgh, PA (Zone 6b)
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Plant Oklahoma Red Onion
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Oklahoma Red Onion
Around Jul 26≈ 100 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Oklahoma Red Onion dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Best in zones 4-8; grows well in cooler to moderate climates
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Seedling
2-3 weeksThin green shoots emerge from seed or sets; small white roots develop
Keep soil consistently moist but not waterlogged. Thin seedlings to proper spacing. Provide plenty of light. Apply light fertilizer when true leaves appear.
Vegetative Growth
6-8 weeksLong green leaves develop above ground; bulb formation begins underground as day length increases
Maintain consistent watering and nutrient supply. Keep free from weeds. Monitor for pests. Mulch lightly to conserve moisture and suppress weeds.
Bulb Development
4-6 weeksUnderground bulb swells as the plant responds to long day length; layered red scales form
Continue regular watering. Reduce nitrogen fertilizer to encourage bulb development. Keep beds weed-free. Do not hill soil over developing bulbs.
Maturation
2-3 weeksTops yellow and begin to topple over; bulb reaches full size with papery red skin
Reduce watering significantly. Stop fertilizing. Allow tops to dry and cure in place if weather permits. Harvest when 50-75% of tops have fallen over.
Harvest & Storage
Harvest occurs once; storage can last 4-6 monthsBulbs are pulled, cured, and stored with dry papery outer layers
Cure in a warm, dry, well-ventilated location for 2-3 weeks. Store in cool, dry conditions with good air circulation. Check periodically for sprouting or decay.
Common Pests
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Use row covers on young plants. Apply neem oil or spinosad. Remove infested bulbs immediately. Practice crop rotation.
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Spray with insecticidal soap or neem oil. Increase humidity with overhead watering. Remove heavily infested plants.
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Use fine mesh row covers. Apply pyrethrin-based insecticides. Remove plant debris promptly. Rotate crops.
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Improve air circulation. Avoid overhead watering. Apply copper fungicide if needed. Remove affected foliage.
Uses
Fresh eating and grilling
CulinaryOklahoma Red onions have a mild, slightly sweet flavor perfect for eating raw in salads, salsas, and sandwiches, or grilled whole and caramelized. Their relatively low sulfur content makes them less pungent than white onions. [source]
Long-term storage
CulinaryThis variety is prized for its exceptional storage qualities, keeping 4-6 months in cool, dry conditions. Its dry, papery skin and dense flesh protect it from spoilage. [source]
Natural dye
HouseholdThe red-purple outer layers of Oklahoma Red onions can be used to create natural dyes for fabrics and crafts, producing shades of red and rust depending on mordant used. [source]
Antioxidant and anti-inflammatory properties
MedicinalRed onions contain quercetin and anthocyanins, compounds with potential antioxidant and anti-inflammatory benefits when consumed regularly. [source]
Pollinator support during flowering
WildlifeIf allowed to bolt and flower, onion plants produce globe-shaped flower heads that attract bees and beneficial insects during bloom. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Harvest when 50-75% of the tops have fallen over and begun to dry, typically mid to late summer. Gently pull bulbs and lay them in a single layer in a warm, dry, well-ventilated area to cure for 2-3 weeks. The papery outer skin should be dry and intact. Store in cool (50-55°F), dry conditions with good air circulation; Oklahoma Reds can keep 4-6 months.
Fun Facts
- 🌱 Oklahoma Red is an heirloom variety developed in Oklahoma during the early 1900s and remains a preferred long-day onion for northern growing regions due to its reliable bulbing and exceptional storage potential.
- 🌱 The deep red color of Oklahoma Red onions comes from anthocyanin pigments (the same compounds found in blueberries), which increase in concentration as the bulb matures.
- 🌱 A single Oklahoma Red onion plant can produce a bulb weighing 8-12 ounces under ideal growing conditions, making it one of the larger red onion varieties available.
Gardening Terms
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