This showy perennial is usually unbranched but may exhibit some branching.
The erect, 2-3 ft., stems produce lavender-blue, tubular flowers crowded together on the upper stem. Showy, bright blue flowers are in the axils of leafy bracts and form an elongated cluster on a leafy stem. Each flower is split into two lips – the upper lip has two segments and the lower lip has three.
This blue counterpart of the Cardinal flower (Lobelia cardinalis) is a most desirable plant for woodland gardens especially since it blooms bright blue in late summer. The unfortunate species name, siphilitica, is based on the fact that it was a supposed cure for syphilis.
Cold, moist stratification. Start at least 5 weeks before outdoor night temperatures are reliably in the 50 F range. Place seed on the surface of a slightly moistened, sterile, soil-less growing mix. Put this in a labelled, sealed plastic bag and store in a refrigerator for one day. The next day place this in the freezer for one day. Repeat this for one week, alternating between the fridge and the freezer. After stratifying, place mixture on the surface of pots filled with growing media. Seed needs light to germinate, do not cover after planting. Keep moist but not soggy and very warm 70 F. When seedlings are 5 2 inches tall or more, transplant into the garden spaced 1 foot apart.