Black-eyed Susan

Rudbeckia hirta

North American native daisy with rich golden-yellow petals around a dark chocolate central cone. Peak bloom from midsummer well into autumn.

Hardiness ratings

Black-eyed Susan hardiness across the four zone systems
SystemRatingTemperature rangeHow to read it
USDA hardiness zone Zone 3–9 −40 °C to −1.1 °C Zones where it can be grown as an annual — not a frost-tolerance rating
RHS hardiness rating H7 down to −20 °C Plant needs at least this level of cold tolerance
Canadian plant hardiness zone Zone 3–8 −34 °C to −1 °C Zones where it can be grown as an annual — not a frost-tolerance rating
Australian (ANBG) zone Zone 2–6 −10 °C to 15 °C Zones where it can be grown as an annual — not a frost-tolerance rating

As a tender annual, Black-eyed Susan doesn't overwinter — the zone range shows where the growing season supports it. See the RHS rating for its actual cold tolerance.

Growing notes

  • Peak flowering July–September — runs straight through high summer from the solstice towards the equinox
  • Behaves as a short-lived perennial or biennial — self-seeds reliably to perpetuate itself
  • Drought tolerant once established — excellent prairie and meadow plant
  • Cultivars include ‘Goldsturm’ (often listed under R. fulgida) for a more reliably perennial form

Categories

Related plants

Cross-check Black-eyed Susan against your zones

Reference

Black-eyed Susan on Wikipedia