Hydroponics is a method of growing plants without using soil. In this methods plants are grown in a water based, nutrient rich solution. It does not require soil and hence the root system is supported using an inert medium. The ideal humidity level in hydroponics is 50%, however, the humidity may go as high as 70% without serious adverse effects.
The humidity in the greenhouse is monitored using digital meters. For increasing the humidity, small trays with stone bits are filled with water to cover the stones and left between the plant rows. As the water evaporates it will increase the air humidity. Similarly if the marble or stone chips are placed under the plant trays the chips may absorb water and reduce the humidity.
For humidity reduction doors, roof and side vents may be opened using automated or manual openers. Regulation of humidity is prompted through exhaust fans. During the rainy days humidity is a serious issue, any ventilation activity can bring in all the moisture from outside. In the rainy season higher humidity inside the shed minimize the flower pollination as the flowers don’t blossom and the bumble bee doesn’t come out either.
Hydroponic greenhouses should not be ventilated by opening the doors and other vents as this allow the insect pests to enter the shed and damage the crop. Ventilation should be done by using fans that are 5 to 6 ft. high to draw air through and over the plants. Humidity encourages fungus growth whereas the low humidity causes dehydration of plants, so ambient humidity must be maintained.