Lobelia siphilitica (Blue cardinal flower, Great blue lobelia)

Photo/Illustration: Courtesy of Bluestone Perennials

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Botanical Name: Lobelia siphilitica lo-BEE-lee-ah sif-il-IT-ih-kah Common Name: Blue cardinal flower, Great blue lobelia Genus: Lobelia

This clump-forming perennial has upright leafy stems. From late summer to mid-autumn, it bears dense spikes of light to bright blue tubular, two-lipped flowers with a more prominent lower lip.
Noteworthy characteristics: Long-lasting bloom. Suitable for edging, near water, or in a mixed or herbaceous border. U.S. native.
Care: Grow in deep, moist soil. Fertilize every two weeks in spring and early summer to improve flowering. Plants may be trimmed as they die back in hot summers.
Propagation: Divide in summer. Take bud cuttings in midsummer.
Problems: Rust, smut, leaf spots, and slugs.

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Photo/Illustration: Courtesy of Bluestone Perennials

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