Loose-leaf lettuce
Lactuca sativa is suitable for hydroponic self-sufficiency in DWC, NFT or Kratky systems.
Why this crop is worthwhile
Short crop cycles and staggered harvests make loose-leaf lettuce useful for a steady supply. The question is not only whether a plant grows hydroponically, but also whether its edible proportion, growing time, light requirements, workload and storage life suit the household.
System and root space
DWC, NFT or Kratky is recommended. The root zone must remain evenly moist, well aerated and protected from light. Record the source water and nutrient solution; returns, pipes and reservoirs must remain accessible and easy to clean.
Relevant system pages: Deep Water Culture (DWC) · Nutrient Film Technique (NFT) · Kratky method
pH, EC and climate
A cautious starting range is pH 5.5–6.5 and EC 1.2–2.0 mS/cm at 15–22 °C. These are not universal target values: the cultivar, age, light, source water, temperature, measurement method and growth stage may require adjustments.
Sowing and crop management
Staggered sowings provide more even quantities than one large planting. Run a small preliminary trial to check germination and behaviour in the system. Space plants approximately 18–25 cm apart and regularly inspect root health, leaf colour, pests and even water distribution.
Harvesting and storage
Harvest the outer leaves or the entire head. For storage, refrigerate briefly and use fresh. Process only healthy, clean plant material and follow the food-hygiene requirements of the chosen preservation method.
Troubleshooting
- Long, soft plants: Check light levels, spacing and temperature.
- Leaf-edge damage or chlorosis: Check not only EC, but also pH, water hardness and the nutrient formulation.
- Brown roots: Investigate temperature, oxygen, hygiene and waterlogging.
- Uneven yields: Compare flow, emitters, plant spacing and cultivars.