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Length of Roots During Hydroponics

By Janet Beal ; Updated September 21, 2017
Hydroponic vegetables develop slightly differently from those cultivated in the ground.

Hydroponic gardening lets many people with no gardening space grow flowers and vegetables indoors. Basic equipment includes a container for soil-free growing medium, a liquid-nutrient tank and a light source. In addition to its spatial flexibility, hydroponics also lower seasonal barriers facing outdoor gardens. Plants grow differently in hydroponic gardens, but the results brighten the gardener and the cook's day.

Passive Hydroponics

So long as liquid rather than soil provides the nutrients, hydroponic gardening takes several forms. Plants in pots filled with inorganic growing medium and fed by means of wicks inserted in the pots meet the description of passive hydroponics. Self-watering pots permit good plant growth, but because plants are still in pots, the roots become pot bound. While technically hydroponic with nutrients provided in liquid

Active Hydroponics

Active hydroponic systems use mechanics to move water and nutrients. From an old aquarium with a small pump to expansive, gravel-based, ebb-and-flow water gardens, active hydroponics provide plants with a steady, nutrient-rich water solution. Plants are contained within soilless medium plugs or anchored in a film covering over a nutrient tank. Both systems make affect root growth.

How Roots Grow in Active Systems

Hydroponically grown plants develop smaller roots than those grown in soil because nutrients and water are so readily available. Roots grow to support the plants, but are no longer the sole support for growth. Collars or growth-medium plugs help hold plants in place and erect, so the roots may not spread as widely below a plant as they would when sustaining a plant upright in hard wind or other weather.

Major Impact on Root Length

The greatest burden taken away from plant roots by a hydroponic system is searching for adequate water. Roots display the same healthy growth as other plant parts but do not show the extensive long growth characteristic of plants with an inadequate or unpredictable water supply. Plants share with other living organisms the ability to survive longer with adequate water and poor food than with adequate food and insufficient water. Shorter roots than found on soil-grown plants indicate the efficient delivery of both water and nutrients to root systems.

Hydroponics and Root Crops

Passive hydroponics are suited growing root crops, such as carrots and beets, turnips and potatoes, all of which do best when adequately watered. It is possible that soil plays a role in shaping and creating the texture of root crops. One gardener describes experiments with planting carrots, radishes and spring onions but notes that the carrots were oddly shaped.


About the Author


Janet Beal has written for various websites, covering a variety of topics, including gardening, home, child development and cultural issues. Her work has appeared on early childhood education and consumer education websites. She has a Bachelor of Arts in English from Harvard University and a Master of Science in early childhood education from the College of New Rochelle.