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Old 03-04-2011, 09:27 PM
GpsFrontier GpsFrontier is offline
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Join Date: Mar 2009
Location: Lake Havasu AZ.
Posts: 1,855

One of the benefits of growing hydroponically is that you can provide better growing conditions than you would be able to in soil. Plants grown hydroponically typically have smaller root systems than those grown in soil. In soil, plants need to expand the root systems in search for the mineral elements they need to grow (as well as moisture). They can only absorb these mineral elements if they are dissolved in the water (soil or hydro). So even though the soil may contain many minerals right next to a root, it still needs to expand in search for some that are already dissolved in the water that's in the soil.

With hydroponics all the mineral elements are already dissolved in the water. Also instead of the plant needing to search out the dissolved minerals, you bring them directly to the roots. Thus the smaller root systems. When the plants roots have all the mineral elements as well moisture brought directly to them, that reduces the energy they need to expend the root system to search them out in order to support the plant canopy (and/or fruit). Less stress results in bigger, healthier, plants and fruits (even with smaller root systems).

Making the roots work to reach the water, as well as the dissolved mineral elements in it that they need to build plant tissue with, just adds stress to the plant. Both in water stress, as well as searching for the mineral elements (food) they need. Sure the roots grow longer faster when you make them reach for food and water. But that's simply because there being deprived from the life supporting water and elements they need to grow the plant. That just diverts energy to the roots that the plant could be using to grow the plant canopy/foliage. Photosynthesis takes place in the plant canopy, and photosynthesis is where all the compounds and building blocks needed to build plant tissue is created. The larger the plant canopy, the more photosynthesis that can take place. Thus, faster growing, healthier plants.

I'm not saying you cant grow nice healthy looking plants by making them work to get what they need (and adding stress), after all that's what they do in soil (nature). Just that I don't see any benefit and/or the point of doing so on purpose.

With that said, in most cases there can be an increased growth rate in the plant canopy by lowering the water level. But this isn't because the roots are getting bigger because they are needing to reach for a water supply (and/or added stress). It's a result of the roots being able to get more air/oxygen (less stress). If the roots are still getting moisture, but then get an increased amount of air they will grow smaller diameter fine roots (even hair like). These smaller roots grow larger, and expand on the overall root system. These smaller hair like roots also absorb much more nutrients than the larger diameter roots. Thus they can support faster canopy growth. This is the principal behind aeroponics. But there's always a point where by trying to get more air to the roots, that can result in not enough moisture (thus water stress). Aeroponics systems provide the best balance of both.
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Last edited by GpsFrontier; 03-05-2011 at 04:04 AM.
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