Lobelia × speciosa 'Sparkling Ruby'

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lobelia 'Sparkling Ruby'

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Synonyms

Lobelia 'Sparkling Ruby'

Herbaceous Perennial
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A tall clump-forming herbaceous perennial, also grown as an annual, with ovate-oblong moderate green leaves, bearing erect terminal spikes of two-lipped tubular, ruby to dark red flowers in summer and autumn.

Position

Full sun, Partial shade

Soil Types

Chalk, Clay, Loam, Sand

Max Height

0.5-1 metres

Max Spread

0.5-1 metres

Size

Time to Maturity
2–5 years
Max Spread
0.5-1 metres
Max Height
0.5-1 metres

Growing Conditions

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

Position

Full sun Partial shade
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)
H4

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Campanulaceae
Native to GB/Ireland
No
Foliage
Deciduous
Habit
Clump forming
Potentially harmful
Harmful if eatenskin irritant. Wear gloves and other protective equipment when handling Wear gloves and other protective equipment when handling. Pets: Harmful if eatenskin irritant. For further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
Genus
Lobelia can be annuals, perennials or shrubs, with simple leaves and showy 2-lipped flowers that may be solitary or in racemes or panicles
Name Status
Accepted

How to Grow

Cultivation

Grow in deep, rich moisture-retentive soil in sun or partial shade. Feed with liquid fertilizer until flowering and low nitrogen during the rest of the season.

Propagation

Propagate by division and seed. Seed can be sown in very early spring but it may not come true to type

Suggested planting locations and garden types

  • Coastal
  • Cottage and informal garden
  • Wildlife gardens
  • Flower borders and beds

Pruning

Cut back after flowering

Pests

May be susceptible to slugs

Diseases

May be susceptible to crown rot