I’m using a wick system in my hydro-garden and I was wondering if the wick can absorb and deliver a sufficient amount of oxygen to the roots? I oxygenate the water by shaking it first, what else should I do?
Wick systems use woven nylon rope to draw water up to the planting medium. The water is drawn up automatically as it is needed to maintain a certain moisture level. Most planting mixes maintain a moisture level sufficient for plant roots to draw upon. The soil should not get soggy because it maintains air space between the particles, allowing for proper drainage. Since water is drawn up to the medium, rather than flooding it periodically, air spaces are maintained continuously and the used air, containing CO2, is exchanged for oxygen rich fresh air.
The wicks are continuously drawing up water, which is held in a thin film around the sides of the nylon threads. This provides a very large surface area in relation to the water depth. As a result there is a tremendous exchange of gasses between the air and water.
In a wick system you don’t have to worry about the roots getting enough oxygen. There is enough air exchange in the container for the roots to obtain adequate amounts of oxygen.
You may find that the roots grow through the container opening and follow the wick down to the reservoir and then start growing a dynamic root system in the water. You will notice that the roots growing in the water are thick, grow fewer branches, and have virtually no root hairs. These roots are adapted for soaking up water/nutrient solution. Their oxygen requirements are probably met by the transfer of oxygen from the roots growing above them along the wick and in the planting mix.
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