How to Grow Double Blackberry
iNaturalist
Double Blackberry
Rubus fruticosus 'Double'
fruitDouble Blackberry is a thornless blackberry cultivar known for its large, sweet berries and exceptional flavor. It produces double flowers and abundant fruit on vigorous, semi-erect canes. This variety is prized for fresh eating, preserves, and desserts.
When should you plant Double Blackberry in your zone?
Get a personalized planting timeline — when to start seeds, transplant, and harvest — based on your USDA zone and local frost dates. Free to start.
Example Double Blackberry timeline · Pittsburgh, PA (Zone 6b)
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Plant Double Blackberry
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 Blackberry
Late summer into fallBefore the first fall frost (≈ Nov 8)
Sample dates for Pittsburgh, PA. Sign up to get exact Double Blackberry dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 5-9, with best production in zones 6-8
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Get my Double Blackberry timeline →Growth Stages
Establishment Year
Spring through fall of first yearNew canes emerge and establish root system; minimal flowering expected
Keep consistently watered, mulch heavily, remove any flowers to encourage root development
Cane Development
Late spring through early summer, year 2+Vigorous upright and semi-erect canes grow rapidly, reaching 6-8 feet tall
Provide trellising or support, prune to maintain shape, remove weak or damaged canes
Flowering
Late spring to early summer, 3-4 weeksDouble flowers (often with extra petals) appear in clusters, white to pale pink
Ensure adequate light and nutrients, maintain consistent watering during this stage
Fruiting
Mid-summer, typically 4-6 weeksLarge berries develop from flowers, progressing from green to red to black over 4-6 weeks
Continue regular watering, monitor for pests, support canes as berries add weight
Dormancy
Fall and winterCanes harden off as temperatures drop; plant prepares for winter
Prune out old fruiting canes, apply winter mulch in colder zones, minimal watering
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Hand-pick in early morning, use row covers, apply neem oil or insecticidal soap
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Prune and destroy infested canes, maintain plant vigor, remove dead wood promptly
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Increase humidity, spray with water, use horticultural oil or neem oil if severe
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Remove infested berries, use pheromone traps, apply spinosad in early bloom
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Remove infected leaves, maintain air circulation, apply insecticidal soap as needed
Uses
Fresh eating and desserts
CulinaryLarge, sweet berries are excellent fresh from the bush, in salads, smoothies, pies, and cobblers. The mild, complex flavor without excessive tartness makes them ideal for premium dessert applications. [source]
Jams, preserves, and wine
CulinaryHigh pectin and sugar content make Double Blackberry excellent for jam, jelly, and cordial making. The abundant harvest allows for bulk preservation. [source]
Immune and digestive support
MedicinalBlackberries are rich in vitamin C, polyphenols, and fiber that support immune function and digestive health. Traditional folk medicine uses berries and leaves for digestive complaints. [source]
Dye production
HouseholdBlackberry leaves and unripe berries can be used to create natural dyes for textiles, producing shades of gray, brown, and purple depending on mordant used. [source]
Wildlife habitat and food
WildlifeCanes provide excellent shelter for beneficial insects and small wildlife; berries feed birds and pollinators. Thornless variety reduces defense mechanisms but is less wildlife-dependent. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Pick berries when fully black and slightly soft to the touch (they do not ripen after picking). Harvest in early morning when berries are coolest for best flavor and shelf life. Use a gentle pinching motion to avoid crushing. Peak harvest is typically mid-summer through early fall. Berries will continue producing for 4-5 weeks.
Fun Facts
- 🌱 The 'double' in Double Blackberry refers to its distinctive flowers with extra petals rather than single-petaled blooms, creating a more ornamental appearance while still producing fruit abundantly.
- 🌱 Thornless blackberry varieties were developed in the mid-20th century, making picking significantly easier and less painful than traditional thorny varieties, while maintaining excellent flavor.
- 🌱 Blackberries were traditionally used by Native Americans and early settlers for food, medicine, and dye-making, and remain one of the most productive perennial fruit crops in home gardens.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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