Flowering & Reproductive Development

Flower Microclimate & Disease Risk

Temperature, humidity, leaf wetness, airflow, and tissue density inside flowers can differ from room or weather-station measurements. Disease risk must therefore include the microclimate at the susceptible tissue.

Key concepts

  • Dense inflorescences can retain humid air
  • Condensation can occur on tissue even when room RH seems acceptable
  • Dead floral tissue can become a colonization site
  • Airflow at the room scale may not penetrate dense clusters

What to measure or observe

  • Inspect flower interiors
  • Record overnight temperature/RH
  • Check for condensation after cool periods
  • Map disease onset by canopy and flower density

Common mistakes

  • Inspecting only flower surfaces
  • Using daytime room RH as the entire disease-risk assessment
  • Blaming density without checking moisture and pathogen evidence
  • Compressing flowers with support netting

Visuals this lesson still needs

  • Flower microclimate cutaway
  • Room-versus-flower RH concept
  • Condensation sequence
  • Botrytis risk inspection map