Blue vervain, or Verbena hastata, is a native perennial that rises two to five feet tall on stout, square, grooved stems. Its narrow, lance-shaped leaves grow in opposite pairs and are sharply toothed, lending a rugged appearance to its form. But it’s the flowers that truly define this plant—slender, pencil-like spikes of vivid blue-purple blooms that appear in midsummer and often persist into early fall. This plant can be found in wet prairies, damp thickets, and along streambanks.
Ecologically, blue vervain is a quiet powerhouse. It plays a vital role in supporting pollinators and other wildlife, offering both nectar and habitat. Among its most important relationships is its role as a larval host plant. The common buckeye butterfly lays its eggs on blue vervain, and its caterpillars feed on the foliage. The verbana moth also depends on this plant during its larval stage.
The flowers are a magnet for a wide array of pollinators. Long- and short-tongued bees, including halictid bees, eucerine miner bees, and epoline cuckoo bees, regularly visit the blooms. Butterflies, bee flies, thick-headed flies, and thread-waisted wasps also frequent the plant, drawn by its rich nectar stores. Even golden soldier beetles, which help control garden pests, are known to visit. This diversity of insect visitors makes blue vervain a keystone species in pollinator gardens, especially during the late summer months when other nectar sources may be scarce.
Beyond insects, blue vervain also supports birds. Its seeds are a valuable food source for song sparrows, swamp sparrows, field sparrows, slate-colored juncos, and northern cardinals. In winter, when food is limited, the plant’s seedheads continue to offer sustenance, while also adding texture and visual interest to the landscape.
In the garden, blue vervain is both beautiful and functional. Its tall, torch-like flower spikes provide vertical structure and a vivid splash of color, pairing well with other prairie natives like coneflowers and black-eyed Susans. It thrives in moist soils and tolerates periodic flooding, making it ideal for rain gardens, bioswales, and low-lying areas. Its adaptability to wet conditions also makes it a valuable plant for restoration projects, where it can help stabilize soil and outcompete invasive species like purple loosestrife.
Gardeners will appreciate its low-maintenance nature. Blue vervain is resistant to deer and rabbits, thanks to its bitter foliage, and it is generally free from pests and diseases. While it can self-seed, it does so modestly and is not aggressive, making it a reliable and well-behaved addition to native plantings. (July)
