Riddell's Goldenrod (Oligoneuron riddellii)

Local Name: Riddell’s Goldenrod

Botanical Name: Oligoneuron riddellii (syn. Solidago riddellii)

Family: Asteraceae (Solidago sect. Ptarmicoidei)

Native Status: Minnesota Native

Landscape Archetype: Prairie, Grassland, Wetland

Life Cycle: Perennial

Sun Exposure: Full sun

Soil Moisture: Mesic, Wet

Soil Type: Loam, Silt, Clay‑loam, Peat‑influenced soils

Height & Width Range: Height: Shoulders (36"–48"), Width: 18"–24"

Bloom Color: Yellow

Morphology Notes: An upright goldenrod with distinctive bent or arching stem leaves that are narrow, grasslike, and prominently 3‑veined. Stems are smooth and unbranched until flowering. Inflorescences form dense, flat‑topped clusters of small yellow composite heads arranged along stiff, ascending branches. Blooms late summer into fall. Root system is fibrous with short rhizomes enabling slow clump expansion.

Fruits and Seeds: Dry achenes topped with white pappus, maturing in fall. Not edible. Not known to be toxic. Dry seed clusters retain some ornamental texture, catching low autumn light. Goldenrods do have some medicinal properties in leaves and roots, consult other sources prior to consuming.

Habit and habitat: A clumping, upright, stiff‑stemmed prairie goldenrod found in wet–mesic to mesic tallgrass prairies, sedge meadows, prairie fens, swales, and moist prairie edges. Often occurs in high‑quality prairie remnants with deep soils and moderate groundwater influence. Strongest and most vertical in full sun; may lean in partial shade or overly rich soils. Handles seasonal flooding and historical disturbance such as fire and moderate grazing. Forms tight but expanding clumps without becoming aggressively colonial.

Companions: Porcupine Sedge (Carex hystericina), Fowl Manna Grass (Glyceria striata), Switchgrass (Panicum virgatum), Swamp Milkweed (Asclepias incarnata), Common Boneset (Eupatorium perfoliatum), Bottle Gentian (Gentiana andrewsii), Swamp Aster (Symphyotrichum puniceum), Prairie Blazing Star (Liatris pycnostachya), Blue Vervain (Verbena hastata), Stiff Gentian (Gentianella quinquefolia).

Ecological Associations: Riddell’s Goldenrod functions as a late‑season keystone in wet–mesic prairie systems, drawing in a wide guild of insects that rely on fall nectar before dormancy or migration. Bumble bees are frequent visitors, along with sweat bees (Lasioglossum spp.), mining bees (Andrena spp.), syrphid flies, tachinid flies, soldier beetles, and butterflies including Painted Lady (Vanessa cardui) and migrating Monarchs (Danaus plexippus). Beyond its pollinators, the plant supports specialist goldenrod‑feeding micromoths and leaf‑mining larvae documented on Oligoneuron and Solidago species, tying it into a broader Asteraceae herbivore network. Its upright flowering structure provides hunting perches for crab spiders (Misumena vatia) and ambush bugs (Phymata spp.), while the foliage and stems harbor leafhoppers, planthoppers, and juvenile Orthoptera that inhabit warm, damp prairie soils.

Provenance: MN

NH Propagation technique: Seed

Special Powers: One of the most architectural goldenrods, Riddell’s adds late‑season strength and clarity to moist prairie plantings with its vertical stance and clean, flat‑topped bloom structure. It supports insects during a seasonal bottleneck, fuels monarch migration, and holds its form beautifully into autumn. Tough, elegant, and ecologically generous, it’s a natural fit for prairie and meadow matrices that need late color and reliable pollinator energy. Add it to rain gardens, low laying sunny spots, wet land edges or if you lucky enough to have a ground water fed fen, try it in moderation.