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BogsHerbaceous Perennial

Lobelia cardinalis

cardinal flower

An erect, clump-forming herbaceous perennial to 90cm in height, with rather glossy bright green oblong leaves and brilliant scarlet, two-lipped flowers 5cm in length in terminal spikes

Other common names
bog sage
hog's physic
see moreIndian pink
red bay
scarlet lobelia
slinkweed
water gladiole
brilliant lobelia
Synonyms
Lobelia cardinalis scarlet
Lobelia splendens
see moreLobelia fulgens

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Size
Ultimate height
0.5–1 metres
Time to ultimate height
2–5 years
Ultimate spread
0.1–0.5 metres
Growing conditions
Loam
Moisture
Poorly–drained
pH
Acid, Alkaline, Neutral
Colour & scent
StemFlowerFoliageFruit
Spring Green
Summer Red Green
Autumn Red Green
Winter
Position
  • Full sun
  • Partial shade
Aspect

South–facing or West–facing or East–facing

Exposure
Exposed or Sheltered
Hardiness
H3
Botanical details
Family
Campanulaceae
Native to GB / Ireland
No
Foliage
Deciduous
Habit
Clump forming
Potentially harmful
Harmful if eaten, skin irritant. Wear gloves and other protective equipment when handling Wear gloves and other protective equipment when handling. Pets: Harmful if eaten, skin 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

Correct

Plant range
N America

How to grow

Cultivation

Grow in deep, fertile, reliably moist soil in full sun or partial shade

Propagation

Propagate by seed sown in gentle heat as soon as ripe, or by bud cuttings in late summer

Suggested planting locations and garden types
  • Cottage and informal garden
  • Flower borders and beds
Pruning

Cut back after flowering

Pests

May be susceptible to slugs

Diseases

May be susceptible to crown rot

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