Sanguisorba canadensis aka White Burnet

Sanguisorba canadensis is a perennial in the rose family. Its common names include American burnet and Canadian burnet. Its native range spans eastern Canada and the eastern United States. It grows in wet meadows, swamps, bogs, and riverside sites. It also occurs on seepage slopes and in thickets. Some US regions list it as rare, threatened, or endangered. These local reports do not establish a global conservation status.

The plant forms upright clumps and grows fast. Garden plants reach about 5–8 feet [1.5–2.5 metres] tall. They spread about 1.6–3.3 feet [0.5–1 metre] wide. Plants take two to five years to reach full size. The green stems are smooth and lack scent. Most leaves sit on the lower half of the plant. Basal leaves reach 1.5 feet [0.46 metres] long. Each pinnate leaf has seven to fifteen narrow, oblong leaflets. Sharp teeth edge the leaflets, whose undersides are paler green. The plant sheds its leaves for winter.

White flower spikes rise on branched stems above the leaves. They bloom from July to October, though timing varies by site. Each spike measures about 0.17–0.67 feet [0.05–0.20 metres] long. The small flowers have no petals. Each has a four-lobed calyx and four long stamens. These stamens give the spikes their soft, brush-like look. Butterflies and other pollinators visit the flowers. Dry fruits follow in fall, each holding one seed. The fruits stay closed when ripe.

Grow Canadian burnet in sun or part shade. It needs soil that stays moist and has moderate fertility. RHS recommends moist soil with good drainage. NC State also records tolerance of standing water and occasional floods. It accepts chalk, clay, loam, and sand. Acid, neutral, and alkaline soils all suit it. Chicago Botanic Garden lists USDA zones 3–7. RHS gives it the cold-hardy UK rating H7. Tall stems often need support. Spreading rhizomes can become a nuisance, so choose its site with care.

Use it in borders, native gardens, rain gardens, or meadow plantings. Its flowers also suit cutting and wildlife gardens. RHS reports few pest or disease problems. It needs no pruning. Divide clumps in spring or autumn to make more plants. Seeds can also start in cold-frame pots in either season. Plants For A Future records a limited food use for leaves. Boil them, then wash away bitterness before eating with salt and miso. That source lists no known hazards or medicinal uses. This does not establish safety for pets.