Plants require water to grow, produce, and survive. One of the methods of getting water to your plants is through drip irrigation. Also known as trickle irrigation, drip irrigation is a method of getting water to plants through a series of thin PVC (plastic pipes) pipes and emitters.
As the name suggests, the water is released slowly in “drips” or “trickles”. This is done through emitters, usually placed close to where the plant roots are.
Drip irrigation helps the farmer or gardener with the opportunity to conserve water and reduce labour that might be required when doing manual irrigation.
How drip irrigation works
“Drip irrigation works by getting water into the root zone of the plant, where emitters are placed to trickle water,” Ram Chirumamilla an expert in irrigation, told Seeds of Gold.
Drip irrigation can work in any field where farming is possible including slopes. The water comes from the source to the plant, usually raised tanks through main pipes, sub-main pipes, and lateral pipes where emitters are attached to drip water at the root zone.
In between the pipes, there are other components such as valves, backflow preventers, pressure regulators, filters, and tubing adapters.
Pipes: These are used to guide water to the drip pipes. They are either made of polyethylene or rigid PVC. They are used for the main and sub-main channels of the drip irrigation system.
Micro tubes: These are the thin pipes often referred to 1.4 inch, spaghetti, or drips that take water from the main and lateral pipes to the emitters or from the emitters to the plants.
Emitters: Emitters connect the micro tubes that serve the purpose of delivering water at a consistent slow rate. The standard rate of delivery, known as the flow rate is measured in gallon per hour or litres per hour and is usually two liters/hour.
Filter: Filters keep dirt from blocking the emitters/micro tubes by filtering out any debris in the water. They are required in all drip irrigation systems and are usually connected close to the water source before it gets to the pipes.
Valves: These are manual or automatic devices that control the flow of water in the drip system. They can be turned on or off to control the time water flows through the system.
Drip controller (timer): The drip controllers in a drip irrigation control when water is released by managing the time automatic valves open and close. This can be set for particular days and times. Drip times are not compulsory in all drip irrigation system setups.
Backflow preventers: Backflow preventers control water from flowing back towards the source.
Flush caps (valves): Flush caps are placed at the end of the drip irrigation system. They make it possible to flush out any dirt from the pipes.
Pressure regulators: Pressure regulators are used for controlling the pressure from the water source to the irrigation system.
According to Ram, drip irrigation systems are categorised into different types. These are based on how they deliver the water to the plants. These different types of irrigation systems are watermatic drip systems, emitter drip systems, porous soaker hose system, and micro misting sprinkler.
The porous soaker hose is a rubber pipe made from recycled rubber from used tires. It has a small diameter and tiny microscopic holes that oozes water when pressured water passes through the pipe.
It is ideal in raised planter containers, narrow beds, and trees. It can be placed in a circle around the base of the tree so that it irrigates the tree’s root zone. Placing the soaker hose along narrow gardens is an excellent way of getting water to the root zones of the plants.
The porous soaker hose can be connected to drip pipes or drip tubings. It serves as an alternative to emitters in a drip system and is easy to install.
The emitter drip system uses a series of drips connected to the drip tubes to get water to the root zones of the plants. Emitter drip systems can be installed above or below the ground.
In the watermatic drip irrigation, micro-spray heads are used instead of emitters. They spray water on the root zones. The advantage of the watermatic system is it can use grey water (water from baths, sinks, washing machines, and other kitchen appliances). This system is ideal for garden trees and shrubs.
Installing drip irrigation systems
“It requires expertise while installing commercial large scale drip irrigation systems. It is possible to design and install your own drip irrigation system,” says Ram.
When you embark on installing your own drip irrigation system, make sure you spend time planning so as to make sure your drip system meets your requirements and can grow as your garden or field expands and your plants grow.
Below are some of the factors to consider when designing a drip irrigation system:
Pipe length, size, and elevation: The pipe length, size, and elevation changes will determine the requirements for your drip irrigation system as they affect the pressure required and flow rate.
Water requirements for the plants: Plants with the same water requirements should be placed on a connection with the same valve so as to meet their requirements.
When planning your garden or field, it is advisable to propagate these plants with similar requirements in a way that they will be served by a connection with a valve that releases enough water for them.
Growth and expansion: It is advisable to design the system in a way that it will meet the future requirements of the plant. As the plant grows, so does the root zone of the plant.
Why use drip irrigation
This makes sure that water gets to where it is intended. This way water is not spent on areas where plants are not growing as with other irrigation methods that irrigate the whole piece of land, for example, flood irrigation and sprinkler irrigation.