Agastache ‘Blackadder’

Giant Hyssop 'Blackadder'

Agastache ‘Blackadder’ is a hardy perennial producing upright stems with aromatic green foliage and tall spikes of violet-purple to blue flowers from July to October. Reaching up to 1m, it fills borders with height and colour across the season. Fragrant, generally pest-free, and loved by pollinators, it is a valuable addition to Irish cottage and gravel gardens.

Flowering Months

Jan J

Feb F

Mar M

Apr A

May M

Jun J

Jul J

Aug A

Sep S

Oct O

Nov N

Dec D

Size

Max Height

0.5 m — 1.0 m

Max Spread

0.1 m — 0.5 m

Growth Habit

Densely branched plant with compact, leafy, rounded overall shape.

Planting Position

Sunlight i Indicates how much direct sunlight the plant needs each day. Full sun means 6+ hours, part shade is filtered or morning sun, and full shade is little to no direct sun.

Full Sun

Aspect i Aspect refers to the direction the planting spot faces (north, south, east or west). It affects light levels, warmth and exposure.

South West

Exposure i Exposure describes how sheltered or exposed a plant’s position is, particularly to wind and weather.

Sheltered

Hardiness i Hardiness indicates how well a plant tolerates cold conditions outdoors. Higher ratings generally mean greater frost tolerance.

(−10 to −5 °C) Hardy in most of Ireland

Ideal Soil Conditions

Soil Type i Soil type describes the texture of the soil (clay, sand, loam, chalk). This affects drainage, nutrients and how roots grow.

Chalk Loam Sand

Soil Moisture i Soil moisture tells you how wet or dry the soil should be for best growth. Match this to your garden conditions for healthier plants.

Free draining

Soil pH i Soil pH measures how acidic or alkaline the soil is. It affects nutrient availability and can impact plant growth.

Acid Alkaline Neutral

Plant Uses & Merits

Uses

Banks / Slopes
Flower Borders

Merits

Fragrant
Generally pest-free
Loved By Pollinators

Agastache ‘Blackadder’ Description

Planting Guide for Agastache ‘Blackadder’

Standard shipping normally takes 3-5 days. Next day shipping is available on all domestic orders (for an additional charge). International shipping times depend on the products and destination (estimated at checkout).

Care guide for Agastache ‘Blackadder’

Items must be returned within 30 days after receiving your order. Items must be returned in the same condition in which they were received, be unworn/unused, have any tags still attached, and include all the original packaging.

Uses for Agastache ‘Blackadder’ & Garden Styles it suits

Refunds are processed within 7 days from when we receive the item(s).

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