Deep Water Culture (DWC) — Complete Guide
Deep Water Culture suspends roots in oxygenated nutrient solution. Cheapest hydroponic system to build; ideal for lettuce, herbs, and beginner growers.
BY ROOTLESS FARM
Quick answer
Deep Water Culture (DWC) is a hydroponic technique in which plant roots dangle in an aerated, nutrient-rich solution. It is the simplest recirculating system: a reservoir, an air pump, an air stone, and net pots.
How it works
Plants sit in net pots cut into the lid of an opaque reservoir. Roots grow down through the lid into 15–25 cm of nutrient solution kept at EC 1.0–1.4 and pH 5.6–6.2. An air pump drives an air stone that maintains dissolved oxygen at ≥6 mg/L — without it roots suffocate within 24 hours.
Best plants
Leafy greens (lettuce, kale, chard), herbs (basil, mint), and fast fruiting crops (cherry tomato, peppers) thrive. Avoid root crops.
Build cost
Hobby 4-plant tote: $50–80. 20-plant 4×4 raft: $200–400.
FAQ
3 entries- Q01How long do plants take to grow in DWC?
- Lettuce reaches harvest in 28–35 days from transplant; basil in 35–45 days; tomatoes in 70–90 days.
- Q02What is the ideal water temperature for DWC?
- 18–22 °C. Above 24 °C dissolved oxygen drops sharply and root rot risk rises.
- Q03Do I need an air pump for DWC?
- Yes — except in the Kratky variant. A 4 L/min air stone keeps DO above 6 mg/L for most plants.