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Lobelia siphilitica

blue cardinal flower

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Displaying an upright and clump-forming habit, this deciduous herbaceous perennial boasts finely toothed, lance-shaped leaves in a refreshing shade of light green. As summer transitions to autumn, Lobelia siphilitica takes centre stage with its enduring spikes of true blue tubular flowers. These vibrant blooms grace sturdy, upright stems, creating an enchanting visual display in reliably moist or boggy garden settings.

How to care for Lobelia siphilitica:

Plant out in reliably moist or boggy soil, or pot up into a pond basket and place at the margins of a pond in shallow water no deeper than 5cm (2"). A low maintenance plant, cut back foliage to ground/water level at the end of the year. Divide congested clumps in early spring every few years. Protect the crown of the plant during winter with a thick, dry mulch.
Flowering period:
  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
Eventual height:
1m
Eventual spread:
0.3m
Position:

Full sun / light shade

Rate of growth:

Average

Soil:

Aquatic / Reliably damp or boggy

Hardiness:

Fully hardy

  • InformationThis perennial dies back to below ground level each year in autumn, then fresh new growth appears again in spring.
  • InformationHumans/Pets: Harmful if eaten; skin irritant

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PL30007579
1 litre aquatic pot
£21.99
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PL30006881
3 × 1 litre aquatic pots
£39.99 £13.33 each
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