Black-eyed Susan

Herbaceous

Black-eyed Susan

Rudbeckia hirta

Also known as: Gloriosa daisy (selected forms), Yellow ox-eye daisy

Herbaceous Asteraceae PollinatorWildlife AttractorBorder PlantOrnamentalBiomass
Hardiness Zone
3-9
Ideal Temp
55–85°F
Survives Down To
-30°F
Life Cycle
Perennial

Black-eyed Susan (Rudbeckia hirta) is a familiar aster-family perennial or short-lived perennial across much of North America, though many garden strains behave as biennials in hot southern gardens. Hairy stems carry rough leaves and golden-yellow ray flowers around a dark brown central cone, typically reaching roughly 2–3 feet in bloom. subtropical and tropical Americas welcome it as a warm-season wildflower where soil drains and air moves—coastal breezes help; stagnant humid pockets invite foliar ugliness. It reseeds freely—design for succession, not shock when volunteers arrive. ☀️💧 Sun and Water Requirements: - Full sun for stiff stems and heavy flower load; partial shade trades flowers for stretchy weakness. - Average, well-drained soil; drought-tolerant once established—overhead sprinklers every night are mildew donations. ✂️ Methods to Propagate: - Seeds: surface sow in spring after last frost danger; thin to avoid fungal pile-ups. - Division of clumps in spring or fall for named perennial selections—wild-type often easier from seed. 🌾 Harvest / Best Use Timing: - Cut flowers at early opening for bouquets; deadhead if you fear self-seeding, leave seed heads if you love finches. - For biomass chop-and-drop, cut stems after seeds mature if you are not collecting—compost hot.

Good Neighbors
  • Echinacea — overlapping pollinators, contrasting petal color, similar cultural needs.
  • Sunflower — taller aster-family neighbor that extends bloom height and shares sunflower bee traffic.
  • Yarrow — filler that tolerates lean soil and extends insect diversity at the same height band.
Known Threats — Organic Solutions Only
Aphids
Aphidoidea
Banded Winged Whitefly
Trialeurodes abutiloneus
Greenhouse Whitefly
Trialeurodes vaporariorum
Japanese Beetles
Popillia japonica
Lettuce Aphid
Nasonovia ribisnigri
Lubber Grasshopper
Romalea microptera
Powdery Mildew
Erysiphales
Root Aphid
Pemphigus spp.