Understanding the greenhouse environment
The protected greenhouse environment The greenhouse environment is designed to allow plants to perform close to their genetic optimum so that the grower achieves maximum...
Category Archives: Systems
Hydroponics systems consist of two parts, the structure and irrigation system. Structures can be made of various materials such as glass, shade net etc. The irrigation system is either ‘open’ or ‘closed’.
Solution heating of a tomato crop has limited effect on early yields
Heating the nutrient solution of a NFT hydroponic system may sound like a lucrative option for early yields. Tampering with the nutrient solution temperature is...
How to design a hydroponic stock solution system
Proportioner systems Open hydroponic systems lend themselves to two different automation systems i.e. proportioner and injector systems. First let look at what a proportioner does....
Is your closed hydroponic farm correctly designed for stock solutions
Most automated systems installed in closed hydroponic systems use injectors rather than proportioners. A simplified diagram of where to install such a system is provided...
Greenhouse heating – 5 facts you should look at
Greenhouse heating can be very expensive, especially if you greenhouse is not optimally set up for heating. There are factors that can be taken into account in...
Calculating pad and fan requirements
The effectiveness of a pad and fan system will not only depend on the design, but also on the wet bulb temperature outside the greenhouse....
Mechanical filtration of nutrient solution in NFT hydroponic systems
Mechanical filtration is not an effective tool to prevent water borne diseases in NFT hydroponic nutrient solutions. It has been found that the total organic...
Flow rate in gravel NFT hydroponic systems – crucial for optimal system performance
The correct flow rate of closed hydroponic systems is critical for optimal growth of plants. The flow rates are important for all types of closed...
Serious diseases found in NFT hydroponic systems
The pythium fungus is one of the serious diseases that growers can encounter in hydroponic systems. The disease can be kept at bay if the...
Differential nutrient removal from hydroponic nutrient solutions
Nutrient removal is quite often neglected in closed hydroponic systems since it is difficult to measure and control. The reason is that not all nutrients are...
Refilling nutrient solutions and refilling frequency
Refilling nutrient solutions are only required when a closed (NFT) system is used. With open hydroponic systems the nutrient solution is not re-used so no refill solution is...
Lime – a cheap way to reduce greenhouse temperatures
Cooling a greenhouse can be just as expensive as heating, well almost. There are some very practical methods that you can use to save money. ...
Insect screens in greenhouses – effective biological control
Insect screens or thermal screens are designed to reduce heat in summer and increase temperatures during the night, but also to reduce the number of insects entering the...
Thermal screens greenhouse cooling – are they effective
Heat is always a problem in greenhouses during summer months and even during winter in some areas. Extreme high temperatures cause stress in plants and...
Evaporative pads – maintenance in commercial hydroponics
The installation of new evaporative pads is expensive. The material should last at least two years if not more. With good regular maintenance, evaporative pads...
