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Agastache 'Blackadder'
hyssop (syn. Black Adder)
Hyssops are great for adding height to a border, with whorls of long-lasting, tiny flowers arranged like a bottlebrush, and pointed,...
The ultimate midsummer bee plant with soft, stubby blue bottle brushes tinged with black- purple -the antidote to sunny orange calendulas
Plant description
They are short-lived though, and may need replacing every few years, especially after a cold or wet winter.
Agastache 'Blackadder' has smoky, violet flowers on long spires from July to October. Try it as part of a Mediterranean scheme or in a sunny, well-drained border among ornamental grasses.
Eventual height & spread
Flowering period
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
Plant features
Position
Full sun
Rate of growth
Average
Soil
Moderately fertile, moist, well-drained soil
Hardiness
Borderline hardy (will need protection in winter in colder areas)
How to care for Agastache Blackadder:
Keep cutting the old stems out to encourage repeat flowers through the summer. Once the flowering period is over, resist the temptation to cut back the faded flower-stems until early spring, as they provide interest in the winter months.
Once established, lift and divide congested clumps in spring. Protect roots during the winter with a thick layer of organic mulch around the root zone.
Please note:
GOES WELL WITH
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