Scientific: Lobelia erinus
Common: lobelia
Family: Campanulaceae
Origin: South Africa

Pronounciation: Lo-BE-lee-a e-RYE-nus

Hardiness zones
Sunset
All
USDA All

Landscape Use: Excellent edging annual for winter flower gardens, mixed borders and mass color, hanging baskets and patio containers.

Form & Character: Herbaceous perennial grown as a winter annual in Phoenix.

Growth Habit: Matting to trailing to 6 inches high.

Foliage/texture: Green to purple green, small lanceolate leaves to 1/2 inch in length. Lobelia leaves are that are slightly serrate, alternate, lower leaves more obovate while upper leaves are more linear; medium fine texture.

Flowers & fruits: Small, terminal clusters of flowers ranging in color from white, pink, magenta, light blue to deep blue/purple.

Seasonal color: Colorful flowers in winter.

Temperature: Lobelia prefers winter temperatures in the 40oF to 70oF range.

Light: Full sun to partial shade, lobelia grows rank in full shade and blooms less too!

Soil: Lobelia grows best in an organic amended soil, yet will tolerate most soil types. In Arizona, good drainage is required and performance is enhanced with additions of a balanced fertilizer containing nitrogen, phosphorus, and potassium.

Watering: Lobelia must have a moist soil, thus frequent waters may be required if winter rains are sparse. Lobelia as a genus is comprised of species that generally prefer acidic, moist soil conditions.

Pruning: None

Propagation: Seed, only sometimes reseeds.

Disease and pests: None, mostly because it is only in southwestern desert landscapes a short while.

Additional comments: Lobelia is an excellent winter accent color plant that mixes nicely as a bedding plant with Dianthus deltoides. There are many cultivated varieties including, 'Cambridge Blue' (powder blue), 'White Lady' (white), 'Crystal Palace' (deep blue/purple), 'Blue Wings' (rich blue), 'Horizon Light Pink' (pink) and several others that have variations of single or mixed colors, white to pink to blue. Lobelia can reseed in moist garden locations.

Lobelia is named for Matthias de Lobel, botanist and physician for King James I of England in the 16th century. Lobelia foliage contains the compounds lobelamine and lobeline. These compounds are similar to nicotine and can cause in humans cardiac problems, vomiting, tremors and paralysis if ingested.