I am a landscape designer and have been purchasing 1000's of spring flowering bulbs from A.D.R. Bulbs for 100's of clients in the last 20 years. The bulbs have always been of top quality and if there were any problems, they have been quick to rectify. My orders are often complicated with many varieties and different amounts and they have always filled and delivered everything on time with the best customer care and attention to detail. The pictures in their catalog and website are beautiful. I have visited their facility in NY and was impressed with all their handling equipment and organization. I would highly recommend A.D.R. Bulbs to anyone in the wholesale trade who wants to purchase quality bulbs and work with genuinely nice people.

Nancy Greenlee , From The Ground Up

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Penstemon digitalis 'Dark Towers' (Ships in Spring)

Beard Tongue

Penstemon digitalis ‘Dark Towers’ brings a bold, modern presence to the perennial border with its deep, glossy burgundy foliage and tall, elegant flower spikes. New growth emerges in rich, near‑black tones, holding its color longer into the season than most dark‑leaved Penstemon selections. In early to midsummer, upright stems carry soft pink, tubular blooms that lighten the plant’s dark base and draw steady pollinator activity. The habit is upright but refined, with strong stems that resist flopping and foliage that maintains its sheen through heat and humidity. Adaptable to full sun and a wide range of soils, ‘Dark Towers’ offers durable performance, long‑season contrast, and a sophisticated color pairing when planted alongside lighter perennials or native grasses.

Description	Price
Bundle of 25 tags	$2.50
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Bulk Box of 25 Roots, #1 Div	$49.25
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Growing and Maintenance Tips for Penstemon digitalis 'Dark Towers' (Ships in Spring)

Planting: Plant in spring or early fall. Set the crown level with the soil surface in well-prepared ground.
Spacing: Space plants 12 to 18 inches apart to ensure good air circulation and reduce disease risk.
Light: Prefers full sun (6–8 hours daily). Too little light can reduce flowering and cause leggy growth.
Soil: Well-drained sandy or loamy soil with a pH of 6.0–7.5. Avoid heavy, wet soils.
Watering: Water regularly during establishment. Once mature, it tolerates drought but benefits from occasional deep watering.
Temperature & Humidity: Hardy in USDA zones 3–8. Protect from harsh winter winds and avoid overly humid, stagnant conditions.
Fertilization: Apply compost or a light dose of organic fertilizer in fall. Avoid high-nitrogen feeds.
Pruning: Deadhead spent blooms to encourage reblooming. Cut back stems in late fall or early spring to maintain shape.
Propagation: Divide clumps in spring or fall. Can also be propagated by seed or basal cuttings.
Pest & Disease: Generally pest-free. Good drainage and airflow help prevent root rot and mildew.