Gentiana linearis aka Narrow Leaf Gentian

Gentiana linearis is a herbaceous perennial: a plant with soft stems that lives for years. It belongs to the gentian family, Gentianaceae. Common names include narrowleaf gentian and bog gentian. It comes from the northeast of North America. Its range includes the southeast of Canada. It also grows in forests at higher elevations in the eastern United States. It lives in cool northern woods and open, damp places. Wild sites include bogs, fens, wet meadows, and stream edges. It also grows in roadside ditches where the ground stays moist.

Mature plants form clumps up to 2 feet (0.61 metres) tall. Each clump can spread about 1 foot (0.3 metres) across. These sizes refer to one clump, not a whole seeded patch. Plants set seed with ease when the site suits them. New plants from seed can spread past the first clump. Leaves grow in pairs on opposite sides of the stems. Each blade is narrow, with a linear to lanceolate shape. This means it looks like a line or lance. Leaves reach 0.25 feet (0.076 metres) long. They reach 0.042 feet (0.013 metres) wide.

Blue flowers grow in groups at the stem tips. Each bloom has a tubular, or tube-like, shape. Flowers measure about 0.083 feet (0.025 metres) long. They bloom from July through September. This brings color in summer and early autumn. The flower groups give the plant its main show. They sit above much of the leaf growth. The slim leaves help gardeners tell this plant apart. The blue blooms provide a second clear clue.

Grow this gentian in full sun and keep the soil moist. It grows best in slightly acidic soil that drains well. Keep the soil moist to wet; do not let it dry out. The plant can cope with ground that stays wet. Missouri Botanical Garden lists it for USDA zones 3–7. Its wild wetland sites help explain what it needs in gardens. Sun alone will not meet its needs without moist soil.

Use it in bog gardens or wet meadow sites. Damp wildflower gardens suit it, and it can grow in containers. Leave room for new plants from seed where a wider patch would fit. It needs little routine care when the site suits it. Missouri Botanical Garden reports no major pest or disease problems. Its blue blooms bring seasonal value to the garden. Its ability to grow in wet soil adds value too.