Not the plant you're looking for? Search over 300,000 plants
Herbaceous Perennial

Agastache 'Blue Boa'PBR
  • RHS Plants for pollinators

giant hyssop 'Blue Boa'

A herbaceous perennial with bright green, aniseed-scented leaves. Spikes of purple flowers are produced from mid-summer tomid- autumn

Join the RHS

Become an RHS Member today and save 25% on your first year

Join now
Buy this plant
Size
Ultimate height
0.5–1 metres
Time to ultimate height
2–5 years
Ultimate spread
0.1–0.5 metres
Growing conditions
Chalk
Loam
Sand
Moisture
Moist but well–drained, Well–drained
pH
Acid, Alkaline, Neutral
Colour & scent
StemFlowerFoliageFruit
Spring Green
Summer Purple Green
Autumn Purple Green
Winter
Position
  • Full sun
Aspect

South–facing or West–facing

Exposure
Exposed or Sheltered
Hardiness
H4
Botanical details
Family
Lamiaceae
Native to the UK
No
Foliage
Deciduous
Habit
Bushy
Genus

Agastache are herbaceous perennials with simple, aromatic leaves and small 2-lipped tubular flowers in whorls forming dense spikes, in summer and autumn; some are rather tender but can be grown as annual bedding

Name status

Accepted

How to grow

Cultivation

Grow in well-drained, fertile soil in full sun

Propagation

Propagate by division

Suggested planting locations and garden types
  • Cottage and informal garden
  • Gravel garden
  • Mediterranean climate plants
  • Banks and slopes
  • Flower borders and beds
Pruning

Remove spent flowering spikes through the season

Pests

Generally pest-free

Diseases

Generally disease-free

Get involved

The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.