Lobelia erinus.
Low-spreading plant that is useful as edging for gardens and pots. Experiment combination plantings with impatiens, and other plants – sometimes also coleus.
FROM HER SUNSET WESTERN GARDEN BOOK:
“Lobelia erinus. Takes about 2 months for the seed in flats to grow to planting-out size. Moist rich soil. Part shade in hot areas, full sun where summers are cool, foggy. Self-sows where adapted.”
NATURE IN JAPAN 