I have worked with A.D.R. Bulbs for almost 5 years now, and my company has sourced bulbs with them for longer than that. Communication is great - from ordering, to deliveries, to follow-ups on final product. I love the quality of the product as well as the service. We plant nearly 100,000 bulbs and A.D.R. keeps the whole process easy for us!

Louise Licata , Bland Landscaping Co.

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Dahlia Cactus 'Black Jack' (Ships in Spring)

Dahlia

Dahlia 'Black Jack' is a semi-cactus dahlia known for its deep burgundy-red blooms, which appear almost black in certain lighting. The long, pointed petals curve slightly inward, creating a dramatic, spiky effect that adds texture and intrigue to garden displays. The flowers, reaching 6-8 inches in diameter, stand out against dark green foliage and sturdy stems. This variety grows to approximately 36-48 inches tall and thrives in full sun with well-drained, fertile soil.

Bulk Box of 25 Bulbs, #1 Size tubers

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Growing and Maintenance Tips for Dahlia Cactus 'Black Jack' (Ships in Spring)

Planting: In spring, plant tubers 3 to 4 inches deep with the eye facing up, once soil has warmed to at least 60°F. Space 18 to 24 inches apart to accommodate their vigorous growth and airflow needs.
Location: Full sun (6–8 hours daily) is essential for strong stems and abundant blooms.
Soil: Fertile, well-drained soil with a slightly acidic to neutral pH (6.0–7.0). Enrich with compost before planting.
Watering: Water deeply once or twice a week, keeping soil evenly moist but not soggy. Avoid watering until shoots emerge to prevent rot.
Temperature: Hardy in USDA zones 8–10. In colder zones, lift tubers after frost and store in a cool, dry place.
Fertilization: Apply a balanced fertilizer monthly or use a slow-release formula at planting and midsummer. Avoid high-nitrogen feeds.
Pruning: Pinch back when plants reach 12 inches tall to encourage bushier growth. Deadhead regularly to promote continuous bloom.
Pest & Disease: Watch for aphids, spider mites, and fungal issues. Ensure good air circulation and avoid overhead watering.
Propagation: Divide tubers in spring, ensuring each division has at least one viable eye.