Lobelia 'Grape Knee-Hi'
A clump-forming perennial to about 90cm, with sturdy, upright, leafy stems bearing light green, softly hairy, lance-shaped foliage. Produces dense spikes of long-lasting, tubular, two-lipped, blue flowers from late summer to mid-autumn
Size
Ultimate height
0.5–1 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
Stem | Flower | Foliage | Fruit | |
Spring | Green | |||
---|---|---|---|---|
Summer | Purple | Green | ||
Autumn | Green | |||
Winter |
Position
- Full sun
- Partial shade
Aspect
East–facing or South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H5Botanical details
- Family
- Campanulaceae
- Native to the UK
- 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
Accepted
How to grow
Cultivation
Plant in deep, fertile, reliably moist soil in sun or partial shade. Protect the crown of the plant over winter with a thick, dry mulch
Propagation
Propagate by division
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Patio and container plants
- Flower borders and beds
Pruning
Cut down faded flower spikes in late autumn
Pests
Diseases
May be susceptible to crown rot
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