Agastache 'Blackadder'

hyssop (syn. Black Adder)

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2 litre pot £17.99
available to order from autumn
Quantity 1 Plus Minus
Buy Agastache 'Blackadder' hyssop (syn. Black Adder): Distinctive violet, bottlebrush flowers

This perennial dies back to below ground level each year in autumn, then fresh new growth appears again in spring.

  • Position: full sun
  • Soil: well-drained, fertile soil
  • Rate of growth: average
  • Flowering period: July to October
  • Hardiness: frost hardy (may need winter protection)

    Hyssops are great for adding height to a border, with whorls of long-lasting, tiny flowers arranged like a bottlebrush, and pointed, aromatic fresh green leaves that are attractive to butterflies. They are short-lived though, and may need replacing every few years, especially after a cold or wet winter. '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.

  • Garden care: Don't cut back the faded flower-stems until early spring, as they provide interest in the winter months. Lift and divide congested colonies in spring.


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Delivery information

Eventual height & spread

Eventual height and spread

Notes on Agastache 'Blackadder'

"The ultimate midsummer bee plant with soft, stubby blue bottle brushes tinged with black- purple -the antidote to sunny orange calendulas"

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Amazing, long flowering time, pollinator heaven!


This Agastache grew to be a large and healthy plant whose purple spires lasted and lasted to early Autumn. It was a particularly attractive plant for all pollinators and so proved a fabulous addition for nature and for it's aesthetic value. The leaves are also great when made into tea!




good for contrast


plant a group/make a group with cuttings


Bristol UK



Use in mixed borders. Tall and stately, mixes well with many colours. Needs little attention. Loved by bees and butterflies. Fully hardy on my well draining chalk soil in the South.




Very good for attracting bees and hover flies.


Unfortunately did not make it through the winter.


South West Middlesex


A statement plant for border or container!


As I have very dry soil in my garden I use this plant in containers. It provides a striking foil when planted with Heleniums -a real zing of a combination. I have also planted it with a variegated Euphorbia 'Glacier Blue' and Echinacea 'White Swan' in a container providing an attractive colour combination. It is easy to place the containers within a border to provide added interest.

Jubilate 3

Cheltenham Gloucestershire.


Well Pleased


The plant was mature and in prime condition and really well packed on delivery. I am always happy with the prompt service I receive from you guys.


West Yorkshire




Best used as a summer long flowering plant as a vertical feature. Attracts bees and butterflies, superb colour and aromatic foliage. What more could you ask for in a summer perennial?




Highly recommended


Have several of this plant around the garden, they flower continuously and are beloved by bees. Need minimal care. Recommend them highly.





4.4 8


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