• 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

Heliotropium arborescens 'Marine'

heliotrope 'Marine'

heliotrope 'Marine'

© RHS

  • Other common names heliotrope 'Marine'

  • Synonyms Heliotropium 'Marine'

  • Family Boraginaceae

  • Genus Heliotropium can be annuals, perennials, sub-shrubs or shrubs, with simple leaves and large clusters of small, scented flowers in summer

  • Details 'Marine' is a compact cultivar, usually grown as annual bedding, growing to about 45cm tall, with scented, deep violet-blue flowers

Characteristics

  • Foliage Evergreen

  • Habit Bushy

  • Fragrance Flower

  • Toxicity All parts of the plant are toxic by ingestion

  • 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)

    H1C

Colour

Sunlight

  • Full Sun

  • Partial Shade

  • Aspect South-facing or West-facing or East-facing

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilSand, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Under glass may be grown in a loamless or loam-based compost (JI No3) in full light but with some protection from hot sun. Outdoors grow in any moist but well-drained soil in full sun. Water moderately in the growing season and apply a balanced fertiliser once a month. In the winter keep the rootball just moist

Propagation Propagate cultivars by taking softwood cuttings or semi-ripe cuttings in summer

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

How to care

Pruning Tip-prune shoots on young plants in early spring to promote bushy growth. Older leggy plants can gave their stems shortened by half in spring

Pests Glasshouse whitefly may be a problem if grown under glass

Diseases Generally problem free

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