Hydroponic Harvest
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Growing Lettuce With NFT: The Basics

NFT—nutrient film technique—is one of my favourite ways to grow lettuce. A shallow stream of nutrient solution moves through the channels, feeding the roots while leaving them plenty of oxygen.

How the system works

A reservoir holds the nutrient solution and a pump sends it to the high end of each channel. Gravity carries a thin film past the roots before the solution returns to the reservoir.

The goal is steady flow, not deep water. The roots should have access to nutrients, water and air at the same time.

What to watch every day

Check that every channel is flowing, the pump sounds normal and no roots or debris are blocking the return. Watch the plants as closely as the meters—leaf colour and growth habit often warn you early.

  • Check reservoir level
  • Confirm flow through every channel
  • Watch water temperature
  • Inspect roots for healthy colour and smell

Keep changes gradual

Large, sudden corrections can stress a recirculating crop. Make small adjustments, allow the solution to mix and test again before changing more.

Keep growing

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