Anchusa officinalis

RHS Plant Profile
alkanet

Save a plant

Where do you want to save Anchusa officinalis?

Plants I own
Wishlist
Go to My Plants
alkanet RHS

Other common names

oxtongue

Synonyms

Anchusa leptophylla W.D.J. Koch
Anchusa osmanica
Anchusa angustifolia

Annual Biennial
Buy this from Plant Nurseries
2 Suppliers

Typically biennial (occasionally perennial), producing many spikes of attractive blue flowers from mid-summer to first frost

Position

Full sun

Soil Types

Chalk, Clay, Loam, Sand

Max Height

0.5-1 metres

Max Spread

0.5-1 metres

Size

Time to Maturity
1–2 years
Max Spread
0.5-1 metres
Max Height
0.5-1 metres

Growing Conditions

Chalk Clay Loam Sand
Moisture
Moist but well–drained
pH
Acid or Alkaline or Neutral

Position

Full sun
Aspect
South–facing or East–facing or West–facing
Exposure
Exposed or Sheltered
Hardiness

Hardiness Ratings

All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets

  • H1A: under glass all year (>15C)
  • H1B: can be grown outside in the summer (10 - 15)
  • H1C: can be grown outside in the summer (5 - 10)
  • H2: tolerant of low temperatures, but not surviving being frozen (1 to 5)
  • H3: hardy in coastal and relatively mild parts of the UK (-5 to 1)
  • H4: hardy through most of the UK (-10 to -5)
  • H5: hardy in most places throughout the UK even in severe winters (-15 to -10)
  • H6: hardy in all of UK and northern Europe (-20 to -15)
  • H7: hardy in the severest European continental climates (< -20)
H6

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Boraginaceae
Native to GB/Ireland
No
Foliage
Semi evergreen
Habit
Bushy
Potentially harmful
Bristles can cause skin irritation. Wear gloves and other protective equipment when handling
Genus
Anchusa can be erect or spreading perennials, biennials or annuals with hairy or bristly foliage and cymes of tubular or salver-shaped, usually blue flowers
Name Status
Correct
Plant Range
Europe to Caucasus

How to Grow

Cultivation

Grow in any modrately fertile, moist, well-drained soil in full sun

Propagation

Propagate by seed in late winter or early spring at 13-16C (55-61F). Root basal cuttings in spring or root cuttings in winter

Suggested planting locations and garden types

  • Flower borders and beds

Pruning

Cut back old stems after flowering has finished

Pests

Generally pest-free

Diseases

May be susceptible to powdery mildews