Lobelia cardinalis growing with Actaea simplex and Tiarella

Lobelia cardinalis

Cardinal flower

A table displaying which months are best to sow, plant and harvest.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Flowers
Flowers

Plant does not flower in January

Plant does not flower in February

Plant does not flower in March

Plant does not flower in April

Plant does not flower in May

Plant does not flower in June

Plant does not flower in July

Plant does flower in August

Plant does flower in September

Plant does flower in October

Plant does not flower in November

Plant does not flower in December

  • Botanical name: Lobelia cardinalis
  • Common name: Cardinal flower
  • Family: Campanulaceae
Flower colour:

Red

Lobelia cardinalis (cardinal flower) is a brilliantly colourful and showy damp-loving perennial that blooms throughout summer and into autumn, brightening the garden at a time when many other plants are finishing for the year. This hardy perennial must have moisture in order to thrive, either in good moisture-retentive soil, a bog garden or even in shallow water at the edge of a pond. Lobelia cardinalis is handsome in both flower and foliage, bearing many brilliant scarlet-red flowers up to 5cm long. The blooms are borne on stems up to 1m tall that rise vertically from a basal rosette of foliage. The leaves are long and slender, bright green tinged with bronze, or purple in the case of named varieties such as ‘Bee’s Flame’ and ‘Queen Victoria’.

Advertisement

Lobelia cardinalis is an herbaceous perennial, dying back to the ground in autumn and regrowing in spring. However, it tends to be short-lived, although dividing the plant every two to three years can extend its life. To do this, dig up the clump in spring, divide into two or more good-sized pieces each with plenty of roots and shoot buds, and replant. Lobelia cardinalis is moderately hardy – in cold areas, protect with a mulch of straw or chipped bark over winter.

Once established, Lobelia cardinalis is trouble free to grow so long as the soil is adequately moist.

Advertisement

Lobelia cardinalis is toxic if consumed. Wear gloves to avoid contact and wash hands well after handling.

This page contains affiliate links and we may receive a commission for purchases made. Please read our affiliates FAQ page to find out more.

Advice on buying Lobelia cardinalis

  • Lobelia cardinalis needs moist soil to thrive. Ensure you have the right growing requirements before buying
  • You may find a Lobelia cardinalis at your local garden centre but you’ll find more choice online
  • Always check plants for signs of disease or damage before buying

Where to buy Lobelia cardinalis

How to grow Lobelia cardinalis

  • Plant size

    100cm height

    30cm spread

  • Aspect

    South facing, east facing, west facing

  • Position in border

    Middle

  • Sun exposure: Full sun, partial shade
  • Hardiness: Hardy
  • Soil type: Clay / heavy / moist

Plant calendar

A table displaying which months are best to sow, plant and harvest.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Flowers
Flowers

Plant does not flower in January

Plant does not flower in February

Plant does not flower in March

Plant does not flower in April

Plant does not flower in May

Plant does not flower in June

Plant does not flower in July

Plant does flower in August

Plant does flower in September

Plant does flower in October

Plant does not flower in November

Plant does not flower in December

Lobelia cardinalis and wildlife

Lobelia cardinalis is known for attracting bees.

Attractive to Bees

Does not attract Beneficial insects

Does not attract Birds

Does not attract Butterflies​/​Moths

Does not attract Other pollinators

Is Lobelia cardinalis poisonous?

Lobelia cardinalis causes an upset stomach.

Toxic to:

Toxic to People

No reported toxicity to:

No reported toxicity to Birds

No reported toxicity to Cats

No reported toxicity to Dogs

No reported toxicity to Horses

No reported toxicity to Livestock