• AGM plants

    AGM plants have been through a rigorous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases

Salvia guaranitica 'Black and Blue'

anise-scented sage 'Black and Blue'

  • Other common names anise-scented sage 'Black and Blue'

  • Family Lamiaceae

  • Genus Salvia can be annuals, biennials, herbaceous or evergreen perennials, or shrubs. They have paired, simple or pinnately lobed, often aromatic leaves and 2-lipped flowers in whorls, forming simple or branched spikes or racemes

  • Details 'Black and Blue' is a tall perennial with a running rootstock, forming a wide clump of stems bearing ovate leaves and loose spikes of dark blue flowers 4cm long, each set in black calyx, and opening in late summer and autumn

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • 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)

    H3

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or West-facing

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureWell-drained

  • SoilSand, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 1.5-2.5 metres

  • Ultimate spread 1-1.5 metres

  • Time to ultimate height 1-2 years

How to grow

Cultivation Best grown in full sun in well-drained soil with shelter from cold winds. Maintain low humidity for plants overwintered indoors in a greenhouse. Under glass grow in well-drained loamless or loam-based potting compost (JI No.2) in full light with shade from hot sun

Propagation Propagate by division of established clumps. Take softwood and semi-ripe stem-tip cuttings from new non-flowering growth. Take basal stem cuttings from new shoots that are about 8cm (3in) tall

Suggested planting locations and garden types Flower borders and beds Wall-side Borders City & Courtyard Gardens Coastal Cottage & Informal Garden

How to care

Pruning Deadhead faded flowers

Pests Slugs and snails may attack young growth. Capsid bug and leafhoppers may be troublesome. Under glass aphids, glasshouse red spider mite and glasshouse whitefly may be a problem

Diseases May be affected by fungal diseases including foot and root rots

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