Hydroponics
/ˌhaɪdrəˈpɑnɪks/
Definition
Hydroponics refers to a plant-growing technique in which roots receive water, oxygen, and dissolved mineral nutrients without using soil as the main growing medium. Plants may be grown with roots directly in nutrient solution or supported by inert materials such as rockwool, perlite, or clay pellets. The key feature is that nutrition comes from a carefully managed water-based solution rather than from soil organic matter and soil particles.
Practical Relevance
- Nutrient control: In hydroponics, mineral levels can be adjusted precisely, so plants receive nutrients in forms they can absorb quickly through the roots. This makes deficiency symptoms easier to trace to the root-zone solution.
- Root-zone oxygen: Healthy growth depends on oxygen around the roots as well as water and nutrients. Systems with poor aeration can limit root respiration, which reduces energy supply for uptake and growth.
- Cleaner disease management: Because no soil is involved, hydroponics avoids many soil-borne pests and pathogens. Even so, waterborne problems such as root rot can spread quickly if sanitation and solution quality are not maintained.
- Propagation and intensive cropping: Hydroponics is widely used for leafy greens, herbs, and some fruiting crops in greenhouses and indoor growing. It also supports research and nursery production because conditions can be kept more uniform from plant to plant.
Related Terms
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Root hair
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Aeration
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Watering
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Fertilizer
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Gas exchange
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