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Jesse Saylor
Lamiaceae
AGASTACHE 'Black Adder'
Black Adder Giant Hyssop, Giant Hyssop
The hybrid hyssop ‘Black Adder’ is a long-blooming plant that attracts plentiful butterflies and bees to the garden. The tall, bushy, herbaceous perennial produces long spikes of dark purple flower buds that open to a powdery violet-blue. It begins blooming in the heat of midsummer and will continue up until frost if regularly deadheaded. Like most members of the mint family, it has fragrant foliage, which smells of anise when crushed.
Full sun is required for best flowering and good performance. This hyssop can be grown in average to dry garden soil, but a well-draining, fertile, alkaline loam will allow it to reach its best. Beware wet, heavy clay soils as these will cause plants to rot, particularly in wet winter weather. One benefit of ‘Black Adder’ is that it is sterile, so it will not toss seeds and sow itself, like other hyssops. This is an ideal plant for any sunny perennial border or butterfly garden.
12 - 6
5 - 9
2a, 2b, 3a, 3b, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24
Perennial
Full Sun
24"-36" / 61.0cm - 91.4cm
20"-26" / 50.8cm - 66.0cm
Summer, Late Summer, Early Fall, Fall, Late Fall
Hybrid Origin
Neutral, Alkaline
Well Drained
Loam, Sand
Drought
Fast
Drought Tolerant, Average Water
Clump-Forming
Summer, Fall
Showy
Purple, Blue Violet
Brown
Green
Yes
No
Single
Medium
Matte
Bedding Plant, Cutflower, Mixed Border
Butterflies
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