How to Grow Onion Candy
Onion Candy
Allium cepa var. cepa 'Candy'
vegetableOnion Candy is a sweet, golden-yellow storage onion variety known for its exceptional sweetness and mild flavor. It produces medium-sized bulbs (3-4 inches diameter) with thin, papery golden skin and a crisp, tender interior. This heirloom variety is excellent for fresh eating, storage, and cooking applications.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-9; adapts well across most of North America
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Growth Stages
Seedling (seed-sown) or Set Establishment
2-3 weeksThin green shoots emerge from soil; roots develop rapidly. Sets planted directly begin producing green shoots within 7-10 days.
Keep soil consistently moist but not waterlogged. Thin seedlings to proper spacing as soon as true leaves appear. Ensure full sun exposure.
Vegetative Growth & Foliage Development
6-8 weeksTall, hollow green shoots form above ground; underground bulb begins enlarging. Plant develops 4-6 leaves; foliage height reaches 12-18 inches.
Maintain consistent soil moisture and fertility. Apply balanced fertilizer every 3-4 weeks. Weed regularly to reduce competition. Mulch lightly to retain moisture.
Bulbing
3-4 weeksFoliage begins to yellow and weaken as energy shifts underground. Bulb swells noticeably; outer layers thicken and turn golden. Plant enters dormancy phase.
Reduce watering gradually. Stop fertilizing. Avoid overhead watering to prevent fungal issues. Watch for yellowing foliage as maturity indicator.
Maturity & Curing
2-3 weeks in ground, then cure 2-4 weeks after harvestFoliage flops over and dies back completely; tops dry and brown. Papery golden skin forms; bulb stops growing. Plant enters true dormancy.
Stop watering once tops fall over. Leave in ground for 1-2 weeks if soil is dry to allow skin to fully cure. Harvest when majority of tops are brown and papery.
Storage & Post-Harvest Curing
2-4 weeks until fully curedBulbs are pulled and laid to cure in a warm, dry location with good air circulation. Outer skins continue drying and papering; green stem dries completely.
Spread bulbs in single layer in shed, garage, or well-ventilated area (65-75°F ideal). Turn occasionally for even drying. Once fully cured and stems are brittle, trim stems to 1 inch and store in cool (50-60°F), dry location.
Common Pests
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Spray with neem oil or insecticidal soap; introduce beneficial predatory mites; maintain adequate irrigation to stress thrips
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Use row covers on young plants; apply diatomaceous earth around base; set onion sets deeper; rotate crops yearly
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Ensure well-draining soil; avoid overhead watering; remove infected plants immediately; practice 3-year crop rotation
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Improve air circulation; avoid overhead watering; apply sulfur fungicide; choose resistant varieties
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Hand-pick in early morning; use row covers on young plants; apply neem oil if severe
Uses
Fresh eating and mild cooking
CulinaryOnion Candy's exceptional sweetness makes it ideal for eating raw in salads, salsas, and on burgers, or caramelizing for deep umami flavor in sauces and roasted dishes. The mild flavor is less pungent than storage onions, making it particularly popular for French onion soup. [source]
Pickling and preserves
CulinaryThe tender flesh and natural sugars of Onion Candy make it excellent for pickling whole or sliced, or incorporating into chutneys and relishes for a sweet-savory balance. [source]
Long-term storage
HouseholdDespite its sweetness, Onion Candy develops excellent storage quality when properly cured, maintaining quality for 5-6 months in cool, dry conditions when stored in mesh bags or breathable containers. [source]
Traditional herbal use
MedicinalLike all onions, Onion Candy contains quercetin and sulfur compounds with potential anti-inflammatory and antioxidant properties traditionally used in folk medicine for immune support. [source]
Natural dye
CraftThe golden-yellow papery outer skins can be used to create natural yellow and golden dyes for fabric and yarn dyeing projects. [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 foliage has fallen over and turned brown/papery. Gently dig or pull bulbs on a dry day. Cure in a warm (65-75°F), dry, well-ventilated location for 2-4 weeks until skins papery and necks completely dried. Trim stems to 1 inch; store at 50-60°F in mesh bags or open containers for up to 6 months. Handle gently to avoid bruising, which reduces storage life.
Fun Facts
- 🌱 Onion Candy was developed as a commercial sweet onion variety specifically to compete with Walla Walla and Vidalia onions, and is sometimes called a 'supersweet' onion due to its high sugar content (8-10% by weight).
- 🌱 The sweetness of onions is inversely proportional to sulfur content in the soil—Onion Candy thrives in low-sulfur soils, which is why it develops exceptional sweetness compared to traditional storage onion varieties.
- 🌱 Onion Candy bulbs can actually be eaten when immature as 'spring onions' or 'scallions' if thinned aggressively during the vegetative stage, providing a milder, more tender alternative to mature bulbs.
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