Skip to Left navigation Skip to Main content Skip to Footer

University of Minnesota Extension
www.extension.umn.edu
612-624-1222

Extension > Garden > Diagnose a problem > What's wrong with my plant? > Annuals and Perennials > Ageratum > Spots on or discolored flowers

Print Icon Email Icon Share Icon

Ageratum > Flowers > Spots on or discolored flowers

1 of 2
  • Powdery mildew 1
  • Powdery mildew 2
  • Powdery mildew 3

Gray Mold
Botrytis cinerea

  • Irregular brown spots on leaves
  • Brown blossoms or petals; flowers drop off prematurely
  • Gray fuzzy mold develops on rotted tissue under humid conditions
  • Disease develops during cool, wet weather
  • More information on Gray mold
2 of 2
  • Gray mold 1
  • Gray mold 2
  • Gray mold 3

Aster Yellows
Phytoplasma

  • Part or all of the leaves may turn yellow
  • Flowers fail to develop, remain small green and may be distorted
  • Clumps of weak shoots known as witches broom develop throughout the plant or on flower stalks
  • More information on Aster yellows

Don't see what you're looking for?