Lobelia siphilitica 'Blue Selection'
Great Blue Lobelia or Blue Cardinal Flower Campanulaceae:
Bright blue flowers on 24 to 36 inch (30 in = 76.2 cm) tall stems. Plants will grow well on damp to wet soils or in normal garden soils that do not become overly dry. Attractive plants, blooming in late summer. Plants form low growing rossets of leaves that give rise to showy upright spikes of flowers that bloom over many weeks. In the north, grow plants in full sun to light shade, in the south - grow plants in part to half day shade.
Surface sow seeds, and use 65 to 75F (75F = 23.9C), after two or three weeks if no germination move to 30 to 39F (39F = 3.9C) for four weeks, then back for 65 to 75F (75F = 23.9C). Keep plants moist during the growing season for best flowering.