Description of Lobelia siphilitica f. albiflora (White Cardinal)

Lobelia siphilitica 'Alba' is the white form of great blue lobelia. It likes damp ground and produces upright spires of white flowers in late summer, which look clean and bright in bog planting.

Appearance

It forms sturdy stems with lance-shaped green leaves, then flowers in spikes. Height is often 60 to 100cm depending on moisture and feeding. The flowers are white, sometimes with a faint greenish tint in the throat.

Care Guide

It prefers constant moisture and a bit of shelter from strong wind, as tall stems can lean.

• Sun: Sun to part shade.
• Soil: Rich, moisture-holding soil.
• Water: Keep consistently damp through summer.
• Support: In exposed spots, group planting helps support stems.
• Division: Divide in spring if clumps get big, or let it self-seed in damp soil.

Deadheading extends flowering, but leaving a few stems to seed can give you replacements.

Suitability for Bog Garden

This is a strong mid to back bog plant, especially where you want late summer interest. White flowers also help break up a run of pinks and purples from loosestrife and primulas.

Plant in groups for a fuller look, and keep lower growers in front so the stems don’t look bare at the base.

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