Protected Cultivation

Protected-Cultivation Irrigation & Drainage

Protected structures remove rainfall from the crop but do not remove water-management complexity. Irrigation uniformity, substrate storage, drainage, runoff, root oxygen, and crop demand must be tracked together.

Key concepts

  • Emitter uniformity can change over time
  • Drainage fraction alone does not describe root-zone moisture distribution
  • Protected structures can accumulate salts where natural rainfall never leaches the root zone
  • Standing water and chronically wet floors can increase humidity and sanitation problems

What to measure or observe

  • Catch-test emitters for distribution differences
  • Inspect moisture at several substrate positions
  • Track input and representative drainage EC where applicable
  • Keep floors and drains functioning and observable

Common mistakes

  • Assuming equal irrigation time means equal delivered volume
  • Ignoring clogged or displaced emitters
  • Allowing runoff to pool
  • Using one container as the only irrigation reference

Visuals this lesson still needs

  • Emitter-uniformity test
  • Root-zone moisture cross section
  • Drainage and runoff map
  • Salt-accumulation concept graphic

Connected learning

Use the next piece of evidence

Move between reference material, measurement, field records, and whole-plant context instead of treating one page as the complete answer.