Golden Alexanders produces delicate clusters of bright yellow flowers that bloom from mid-spring to early summer. This species looks like wild parsnip, which is a plant that can cause a skin rash. Golden Alexanders has a shorter growth habit, fewer leaflets, more consistently toothed leaf margins, and an earlier flowering time than wild parsnip. Though these plants are short-lived perennials, they self-seed readily to maintain populations. In full sun to partial shade, golden Alexanders can be grown in moist soils of cottage gardens, native gardens, pollinator gardens, prairies, meadows, and woodlands. This species is native to the Chicago region according to Swink and Wilhelm’s Plants of the Chicago Region and current research.
Size and method of spreading:
Golden Alexanders grows to 1 to 3 feet tall with a 1 to 2 feet spread. These plants readily spread by self-seeding.
Native geographic location an habitat: (include C-value if appropriate)
The native range of golden Alexanders includes the Eastern and Central United States. C Value: 5.
Attracts birds or pollinators:
Though it is capable of self-pollination, golden Alexanders attracts various species of bees, beetles, butterflies, caterpillars, flies, and wasps.
The leaves of golden Alexanders are bright yellowish-green and made up of three to five leaflets (compound leaves). The compound leaves grow around the base of the plant (basal leaves) and alternate up the stems. These leaflets can be up to 2 inches wide and 3 inches long and vary in shape from broad and rounded (ovate) to long and narrow (lanceolate). Some leaves have bases that are slightly heart-shaped (cordate), and the bases of other leaves are typically rounded or broadly tapered. One or two lobes may occur near the bases of leaves. The leaves of golden Alexanders have coarse teeth along their edges (serrate margins). The lower compound leaves have long stalks (petioles), and the upper leaves have shorter stalks or may be stalkless (sessile). The upper leaves sometimes have one to three deep lobes.
Golden Alexanders produces flat-topped or slightly rounded, 2- to 3-inch diameter clusters of tiny, yellow flowers. These clusters are made up of 10 to 21 smaller groups of up to 20 flowers (compound umbels). The flowers have five petals that curl inward. Surrounding the base of the petals are five, tiny, triangular, leaflike structures (sepals). The flowers also have five pollen-bearing structures (stamens) that protrude from between the petals.
Before they mature, the fruit of golden Alexanders are slightly flattened, ovoid to ellipsoid, and green. When they have matured, they turn purple and split into two one-seeded sections that do not open to release the seeds (schizocarps). Each section of the schizocarps has five longitudinal ribs.
As a short-lived perennial, self-seeding can sustain populations of golden Alexanders.
List of pests, diseases, and tolerances:
Golden Alexanders does not have major issues with diseases. Aphids can be pests of golden Alexanders, and the caterpillars of the rigid sunflower borer moth can cause serious damage to the stems.