The word hydroponics is derived from the Latin word that literally means “water working”. Hydroponics is a way of growing plants without the use of soil in nutrient rich solution. Water is enriched by nutrients in the hydroponic system that are similar to that found in soil for conventional gardening. In soil, decomposition of organic matter into the basic nutrient salts provide plants the required substance to feed on. The advantage of hydroponic system is that the nutrients can be controlled and that there are no leeching or runoff of the solution to the environment as it is contained within the system itself. Very little water is lost to evaporation in a hydroponic system, making it very beneficial especially in areas where there is drought.
There are many different systems used in hydroponic gardening. There are two types of hydroponic systems, namely passive and active systems. This is further divided into several types: Flood and Drain (or Ebb and Flow), Deep Water Culture (DWC), Drip feeding, Wick feeding, Nutrient Film Technique (NFT), and Aeroponics. This article discusses the construction of a DIY aeroponics system.
Figure 1. A basic aeroponics system
What Is Aeroponics?
An aeroponics system is the practice of hydroponics gardening that involves plant roots suspended in mid-air inside a chamber that is sprayed with nutrient solution. This type of system allows the roots to absorb oxygen which increases the metabolism and rate of growth (up to 10 times of that soil). Because the system is contained and kept at 100% humidity, there is almost no evaporation or loss of water.
An aeroponics system is almost maintenance free. The plants are held to place with growing medium and you should supply the plants with enough moisture (by watering from the top daily) at the initial stages of growth (about a week) until the spray reaches the roots.
Tools and Materials
- Plastic tote with lid
- Net pots
- 1/2″ x 6″ Poly cut-off nipple
- 3/4″ PVC pipe
- Four 360 degree micro sprayers
- 4″ PVC knockout test cap
- two 3/4″ Slip end caps
- 10\’ Closed cell foam gasket tape
- 3/4″ x 3/4″ x 1/2″ Reducing threaded female PVC tee
- 1/2″ ID transparent blue tubing
- 1/2″ Barbed elbow
- 1 Tube clip
- 7/8″ and 1/8″ Drill bits
- two 7/8″ Hole saw or aviation snips
- Trace the position of the net pots you want to place on the whole system on the lid and cut out the marked area. Apply Foam Tape around perimeter of the inside of the lid.
- Calculate and cut the two 3/4-inch PVC pipes. The length of the pipes should be:
- (length of the inside length of the plastic tote – 6 inch) / 2
- Insert these two pieces of PVC into slip ends of PVC tee. Attach the Slip End Caps on them.
- Along this PVC pipe, drill 4 equally spaced 1/8 inch holes.
- Fit Spray heads on these holes. Do not cut too big a hole first, widen slowly until you attain a fit that is leak proof. Use silicon caulk to seal any leaks if you cut the holes too big.
- Tighten the 1/2″ poly cut-off nipple into 1/2″ female threaded reducing end of the tee the assembly..
- Tighten the whole assembly onto pump outlet. Make sure that you do not overtighten this as it may lead to damage to the pump.
- Place the whole assembly into the reservoir.
- Make a small U shaped cut in one of the plant sites for the outlet for the power cord.
- Fill the reservoir with water and plug the pump in. Turn on the pump and check for function and leakage. Place the lid over the reservoir and allow the system to run for about an hour, checking for leaks every so now and then.
- Once you\’ve made sure that there are no leaks and everything is in working order, place plants into their net pots and place the pots into the lid (where you have traced and cut out one).
- Cover the growing medium around the stems with aluminum foil to keep the humidity in the reservoir.
- Check the nutrient solution periodically as recommended and clean the reservoir after each growth cycle.
Warning: When constructing hydroponics system at home always use PVC, not CPVC. CPVC can leach harmful chemicals into your system.
Before beginning your construction, clean all PVC parts before applying PVC glue to join the parts. This allows the PVC to adhere well and prevents leaks.
Aeroponic growing is a safe and environmentally friendly way of producing healthy plants and crops. An aeroponic system helps conserve water and energy and is a system that uses lower water and energy input per square meter of growing area. It also limits the transmission of diseases from plant to plant because each spray pulse is sterile. The absence of soil also reduces the likelihood of disease spread through growth media.