About
Lobelia laxiflora, the Sierra Madre lobelia, is a herbaceous, woody-based, rhizomatous perennial to 90 cm tall with arching stems bearing long, very narrow leaves and 4 cm long, tubular, red-and-yellow flowers singly in the upper leaf axils in late spring and summer. A rewarding and ornamental Lobelia for a sheltered, moist, sunny border.
About the genus
Lobelia are annuals, perennials or shrubs with simple leaves and showy, two-lipped flowers that may be solitary or borne in racemes or panicles. A versatile and widely grown genus for borders, containers, bog gardens and wildlife gardens.
Growing conditions
SunlightFull sun, Partial shade
Soil typeLoam, Sand
Soil pHAlkaline, Neutral
Soil moistureMoist but well-drained, Well-drained
AspectSouth-facing, West-facing
ExposureSheltered
UK hardinessH3
Plant details
Plant typeHerbaceous Perennial
HabitBushy
FoliageDeciduous
Height0.5-1 metres
Spread1-1.5 metres
Time to full height2-5 years
Suggested usesCity and courtyard gardens, Coastal, Cottage and informal garden
Native toSW USA to Colombia
ToxicityHarmful 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
Care notes
CultivationOf borderline hardiness - protect with a dry winter mulch or lift and store in a frost-free greenhouse. Prefers to be grown in deep, fertile, reliably moist soil in full sun or partial shade
PruningCut back after flowering
PropagationPropagate by semi-ripe cuttings
Pest resistanceMay be susceptible to slugs
Disease resistanceMay be susceptible to crown rot