Diffuse Knapweed

Life Cycle

  • Biennial

Growth Habit

  • Grows up to 2-feet tall, highly branched, bushy

Plant Emergence

  • Germinates in spring or fall
  • Rosettes appear in early spring
  • Flowers summer through fall


  • Individual flowers at branch tips
  • Strong taproot, reproduces by seed


  • Repeated hand removal and grazing can be effective
  • Mowing in bud to flower stage can reduce seed production
  • Apply 2,4-D or Banvel in the rosette stage
  • Apply Curtail, Tordon, or Milestone between rosette and mid-bolt stage