How to Install Drip Irrigation

 Why Use a Drip Irrigation System?

A properly designed and installed drip irrigation system (sometimes called micro irrigation or trickle irrigation) moistens areas where a full lawn sprinkler system fails to reach effectively. A drip irrigation system does this through a series of drippers strategically spaced throughout the target area. The soil type and individual needs of each plant determine the emitter distance and water flow. Because drip irrigation concentrates water in a selected area, it addresses the runoff and evaporation problems inherent in sprinkler systems. The versatility of a drip irrigation system makes it a cost-effective and environmentally friendly solution for both homeowners and professionals.

Drip Irrigation System Design

From the simplest to the most complex, all drip irrigation systems have a few basic things in common: a water source, piping, and emitters. At the water source, begin planning the drip irrigation system. Many systems use a nearby hose bib as the water source, while others use an existing sprinkler pipe. The hose bra option keeps the watering timer, if used, independent of the sprinkler system operating timer. Hose-treated water typically contains less sediment that inhibits leaching than water obtained from irrigation wells. However, it often also contains traces of chemicals used during the filtration and treatment processes.

Next, decide whether you want to run the pipes above or below ground. Hiding drip tubes under mulch or light ground cover visually enhances sensitive areas, such as flower beds and paths. Many gardeners install above-ground drip irrigation pipes. This method allows for ease of maintenance and the ability to replace or remove the emitters without drilling the pipes. Some scenes use a combination of both. A lawn with multiple flower islands will use concrete pipes under the lawn and above-ground pipes in the beds.

A typical drip irrigation system consists of a timer, filter, pressure regulator, tubing adapters, 1/2-inch poly tubing and fittings, emitters, and 1/4-inch tubing. When using a hose bib as a water source, add a backflow preventer. A backflow preventer prevents irrigation water from contaminating the drinking water supply. Pressure relief fittings maintain water pressure at a safe level for plastic pipes, usually 25 psi. 1/2-inch PVC pipe connects to the water supply using a pipe adapter, sometimes called a rotary adapter. Each branch line requires tee and end cap installation. Very large areas often require individual zones that run at different times, using the same zone valves as a standard lawn sprinkler system.

Draw a landscape plan and plan a drip irrigation system. A typical system uses a main line to feed multiple branch lines. The stem line usually extends from the temporary to the center of the irrigated area. Branch lines, when needed, compress the trunk and supply other areas. Mark the location of each emitter on the diagram and circle the emitter coverage. Label each emitter and its type, such as a 0.5 gallon per hour drip or a 10 gallon per hour sprayer at a 180 degree angle. Total emitter flow rate. The maximum flow rate for 1/2-inch poly tubing commonly used in drip irrigation is about 220 gallons per hour. If the calculated flow rate is greater than 220 gallons per hour, either split the system in two or remove enough emitters to reduce the total to less than 220 gallons per hour. Estimate the materials needed using the layout as a guide. Careful planning of drip irrigation systems reduces material waste and overlapping coverage.

A variety of emitters are available for both upstream and downstream applications, including drip heads, micro sprinklers, drip lines and suction lines. Water drips from the drip head, moistening the soil around the plant. Micro sprinklers shoot water into the air like a complete lawn sprinkler system and can cover several feet in every direction. The drip line has evenly spaced ports along its entire length. Football lines run along their entire length. Drip heads and micro sprinklers are measured in gallons per hour, gallons per hour. To help match the system design to the landscape, manufacturers offer precision sprinklers with fully adjustable 90-, 180- and 360-degree nozzles. Gardeners often install multiple types of emitters in a single drip line. This allows them to water many different types of plants, from corn to radishes, on the same line.

Purchase each part individually or purchase a pre-packaged drip irrigation starter kit from the manufacturer. A basic starter kit contains everything needed for a simple system, including a pressure reducer, 1/2" and 1/4" tubing, pipe fittings, and several different emitters. Typically, a starter kit does not contain a timer. Many homeowners find that manufacturers' pre-packaged drip irrigation starter kits are ideal for their irrigation needs. I started using a Rainbird drip irrigation kit in my pepper garden. For my plants, I utilise pots and an above-ground drip irrigation system. This way, I can move plants and irrigation systems to shady areas of my garden during the hot Florida summers and to sunny areas in the winter.

Installing a Drip Irrigation System

Place the drip irrigation system timer, if using, on the water source. Place the timer readout screen in the appropriate position and tighten the timer pull port. Connect the female terminal of the backflow device, if necessary, to the male port of the timer. Connect the pressure reducer and piping adapter. Tighten each connection completely.

Before digging, locate all underground pipes and wires, including any phone wires or cables. If you are unsure of locations, contact the appropriate utility company. Draw a map of the pipes on the ground. If installing a subsurface system, dig trenches for the pipes.

Route a section of 1/2-inch tubing along the main trunk line of the system, working from the swivel adapter on the farthest side. Insert the tubing end of the trunk line into the swivel adapter. Push the tube until its end reaches the back of the fitting. Adjust the position of the pipe as needed, then secure the pipe in place with landscape stakes or staples. Cut the end of the pipe using a PVC cutter and push the end cap onto the pipe or fold the end over and lock it in place with a clamp.

Remove 1 inch of trunk pipe at each branch line. Push each cut end of the stem tube into the tee. Run a section of pipe along the branch line. Push the end of the tube into the remaining port of the tee. Place the tube in place and cut the end of the tube to size. Install the end cap. Repeat this step for every branch line.

Using the schematic as a guide, align the emitters with the tubes. Make a hole in the pipe using a small pipe punch. A micro-pipe punch creates a perfectly sized circular hole. Insert or mount the appropriate emitter into the slot. If running a section of 1/4" pipe, push the 1/4" coupler into the hole and run the pipe as needed. If using stacked sprinklers or independent emitters, insert the fitting at the end of the spray tube into the opening.

Turn on the drip irrigation system and check each fitting for leaks. Tighten any loose parts. If hoses and fittings become disconnected, check the pressure regulator. Inspect and clean any emitters that are not producing water. Adjust the distance and pattern arrangement of each adjustable emitter to match the natural look.

Sometimes the irrigation needs of a vegetable garden change, and branch lines or emitters that were previously useful produce excess water in a particular area. Instead of redesigning your entire drip irrigation system, use insulating plugs to cover redundant and unnecessary drip lines or emitters. If necessary, the plug can be removed later.

Adding a Drip Line to a Sprinkler System

Some areas, such as a narrow row of plants along a path, only need a small amount of water at the root base. Installing a full drip irrigation system would be expensive and unnecessary. However, tapping the tubing under the nearby sprinkler head and running a 1/4-inch drip line or sinker to the problem site will likely fix the problem.

Remove soil around the sprinkler head, exposing the sprinkler system pipe underneath. Remove the sprinkler head from the male pipe adapter. Attach the appropriate microtubing adapter to the male leads. When reusing the sprinkler head, attach the extension riser to the 1/4" barbed port on the male adapter. Install a suitable sprinkler head on the extension lever threads. To finish the sprinkler head, screw a microtube adapter, either single or multi-port, onto the male threads.

Install micropipes along the landscape as needed. Push one end of the 1/4-inch micro tubing onto the barbed fitting of the micro tubing adapter. Repeat this for each piece of microtubule. Connect an emitter to the end of the pipe or attach a sod plug to the end of a section of drip tubing. Install or bury microtubules.

If the extension lifter pushes the top of the sprinkler head too high above the soil surface, either compensate with a smaller head or adjust the depth of the male adapter. If the male adapter connects to the flexible tube, remove some dirt from the bottom of the tube and replace the adapter. If the male adapter is attached to rigid PVC, cut the PVC and install the new adapter at the correct height.

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