How to Grow Double Blue Potato
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Double Blue Potato
Solanum tuberosum 'Double Blue'
vegetableDouble Blue is a distinctive fingerling potato variety with deep purple-blue skin and striking blue flesh throughout. This ornamental yet fully edible potato is prized for its unique appearance, nutty flavor, and excellent nutritional profile due to high anthocyanin content. It produces moderate yields of small, elongated tubers perfect for gourmet cooking and presentation.
When should you plant Double Blue Potato in your zone?
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Example Double Blue Potato timeline · Pittsburgh, PA (Zone 6b)
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Plant Double Blue Potato
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 Double Blue Potato
Around Jun 26≈ 70 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Double Blue Potato dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-8; grows best in cooler climates with adequate moisture
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Get my Double Blue Potato timeline →Growth Stages
Seed Piece Sprouting
2-3 weeksSeed pieces develop sprouts and root systems underground. Early shoots emerge within 1-2 weeks.
Plant seed pieces with eyes facing up in loose, warm soil (ideally 45-50°F+). Keep soil moist but not waterlogged. Ensure good drainage to prevent rot.
Vegetative Growth & Emergence
3-4 weeksShoots push through soil as distinctive blue-purple foliage emerges. Plants grow rapidly, developing compound leaves and branching stems.
Thin to proper spacing once established. Hill soil around stems as they grow to 6-8 inches tall to encourage tuber development and prevent greening. Water consistently. Apply mulch to suppress weeds and stabilize moisture.
Flowering
2-3 weeksPlants produce delicate blue or purple flowers in clusters. This stage indicates underground tuber initiation and bulking.
Maintain consistent watering and soil moisture during tuber development. Continue hilling if not already complete. Flowers can be left on the plant; deadheading is optional and doesn't significantly impact yield.
Tuber Bulking & Maturation
3-4 weeksUnderground tubers enlarge and develop their characteristic deep purple-blue color. Plants become fuller with more foliage. Leaves may begin to yellow if mature-stage is reached.
Maintain consistent moisture and nutrient availability. Reduce nitrogen fertilizer if applied to avoid excess foliage at tuber expense. Monitor for late blight and Colorado potato beetle. Hill soil around stems to prevent light exposure.
Harvest
Ready when foliage dies back naturally (75-90 days total)Plants die back as tubers reach full maturity. Foliage yellows and shrivels; soil dies out. Tubers are ready for harvest, with deep blue color fully developed.
Stop watering 1-2 weeks before harvest to harden skins. Carefully dig with a garden fork to avoid cutting tubers. Cure harvested potatoes in a cool, dark, humid place (50-55°F, 85-90% humidity) for 1-2 weeks before storage.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Hand-pick beetles and egg clusters daily; apply spinosad or neem oil; plant trap crops like borage; use row covers until flowering
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Spray with strong water stream; apply insecticidal soap or neem oil; encourage beneficial insects like ladybugs
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Use reflective mulches; control weeds; apply neem oil; remove infested plants; use resistant varieties if available
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Ensure good air circulation; avoid wetting foliage; remove infected leaves; apply copper fungicide or sulfur preventatively in humid conditions
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Till soil to expose larvae; plant resistant crops in rotation; use beneficial nematodes; maintain soil moisture
Uses
Gourmet Cooking & Presentation
CulinaryDouble Blue potatoes are stunning on the plate, maintaining their vibrant purple-blue color even when cooked. Perfect for mashed potatoes, roasting, boiling, or adding visual interest to salads and grain bowls. [source]
Anthocyanin Content & Antioxidants
MedicinalThe deep purple-blue color indicates high anthocyanin levels—powerful antioxidants linked to reduced inflammation, improved heart health, and better cognitive function. These compounds have been researched for their potential anti-cancer and anti-diabetic properties. [source]
Unique Nutty Flavor Profile
CulinaryDouble Blue potatoes have a distinctive, slightly nutty and earthy flavor that differs from common white or red potatoes. They pair exceptionally well with herbs like thyme, rosemary, and chives. [source]
Ornamental Garden Element
HouseholdWith striking blue-purple foliage and flowers, Double Blue potatoes are visually appealing enough to grow in ornamental gardens alongside traditional vegetables. The plants add color and texture to kitchen gardens. [source]
Specialty & Heritage Potato
CulinaryDouble Blue is a highly sought-after fingerling variety among farmers' market enthusiasts and gourmet restaurants. Growing it at home provides access to premium-quality, nutrient-dense potatoes difficult to find commercially. [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 potatoes 70-90 days after planting when foliage dies back naturally. Gently dig with a garden fork, working from outer edges inward to avoid bruising. Even small potatoes develop full blue color—there's no need to wait longer. For 'new potatoes', harvest earlier (60-70 days) when skins are thin and tender. Harvest in dry weather if possible. Cure potatoes in a dark place at 50-55°F and 85-90% humidity for 1-2 weeks before storage. Store in cool, dark conditions (35-45°F) with good ventilation.
Fun Facts
- 🌱 Double Blue potatoes maintain their striking purple-blue color even after boiling or mashing, making them a favorite for vibrant mashed potato dishes and surprising dinner guests.
- 🌱 The blue and purple coloring comes from anthocyanins, the same pigments found in blueberries, blackberries, and red cabbage—compounds with significant antioxidant and anti-inflammatory properties.
- 🌱 This variety is an excellent choice for home gardeners looking to maximize nutrition per plant; the anthocyanin-rich potatoes rival the antioxidant content of many popular 'superfoods.'
Gardening Terms
New to gardening? Learn about terms used in this guide:
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