Threadleaf coreopsis

A clump-forming native perennial of the carrot family that opens flat-topped, compound umbels of tiny golden-yellow flowers in late spring, when little else is blooming. The toothed, twice-divided-in-threes (biternate) foliage and the bare central flower stalk on each umbel set it apart from other umbellifers. A documented larval host for the black swallowtail and an early-season nectar and pollen source for short-tongued native bees.

A clump-forming aromatic native perennial of eastern North America, grown as much for its silvery floral bracts as its bloom - the upper leaves below each flower head turn a frosted, dusty-mint color in summer. Dense flat-topped clusters of tiny two-lipped pinkish-white flowers cover the plant from mid to late summer and are a magnet for bees and butterflies. Unlike the true mints (Mentha), it spreads only modestly by rhizome and is not invasive.

Whorled milkweed (Asclepias verticillata) is the slenderest and most drought-tolerant of the common native milkweeds, a fine-textured perennial of prairies, glades, and dry open ground across most of central and eastern North America. It grows 12 to 24 inches tall on wiry unbranched stems clothed in narrow, needle-like leaves set in whorls, and carries small umbels of greenish-white flowers from midsummer into early fall, later than most milkweeds. Like all Asclepias it is a monarch host plant, and its late nectar feeds bees and butterflies when little else is flowering. It wants full sun and lean, dry soil, and it is tougher and less bulky than common milkweed, though it spreads by rhizome and can form a wandering colony on good ground. All parts are toxic, and whorled milkweed is one of the more poisonous milkweeds to grazing livestock, so keep it out of pastures and hayfields.

A native eastern North American clump-forming perennial with palmately-lobed foliage and clustered pink-to-purple five-petaled spring flowers. Among the most reliable native woodland perennials for cool-moist sites; tolerates a wide range of conditions and slowly naturalizes by self-seeding.

The native sundial lupine of eastern North American sand barrens and oak savannas - erect 1-2.5-foot stems carry showy spring spikes of blue, pea-shaped flowers above palmately divided leaves of 7-11 radiating leaflets. A nitrogen-fixing legume of dry, sandy, acidic soils, it is the sole larval host for the federally endangered Karner Blue butterfly and the Frosted Elfin, and carries the Xerces Society "special value to native bees and bumble bees" flag.

A low, clump-forming native woodland violet of eastern North America, grown for its early spring blue-to-purple flowers with conspicuous white throats held over glossy, heart-shaped leaves. It does not run, but self-seeds freely - to the point of being weedy in rich, moist ground. A larval host for fritillary butterflies and a nectar source for early bees and butterflies; the leaves are high in vitamins A and C.