Summer in the maritime Northwest typically means lots of sunshine and long, hot stretches without the near-constant drizzle that characterizes our region. Often, we use our summer months to escape into the wondrous landscapes around us. It can be easy to forget that our veggie gardens, colorful containers, and landscape plants need lots of water to thrive when we’re not around, or when it feels too hot to haul out the hose. Additionally, the rainfall we get in spring and autumn is not always consistent enough to keep our plants sufficiently watered–especially trees, shrubs, and perennials that are not yet established, or vegetables and annuals that need regular water to perform well.
While hoses, sprinklers, and watering bags are all excellent ways to water, many gardeners are turning to drip irrigation systems for their manifold benefits: once set up properly, a drip irrigation system is efficient, precise, and a relatively low-effort method for keeping our plants well-watered throughout the year. Setting up your system in spring gives you time to test your system before our dry season begins. This post is meant to serve as an introduction to the key components and setup of a drip irrigation system.
KEY COMPONENTS TO A DRIP SYSTEM
For starters, you will need a standard outdoor spigot, like you would use for a conventional hose. Drip irrigation is not recommended for use indoors with sinks and other faucets.
Timer
The first component of your drip system is a timer. While timers are not required, they allow you to set the system to deliver water at fixed intervals. There are many types of timers available, from simple manual models to more sophisticated automated versions that only require you to set it up, test it, and walk away.
Anti-Syphon
Next comes an anti-syphon. This component is highly recommended, as it ensures that water from your drip system cannot be pulled backwards into your home. Some gardeners may not mind brushing their teeth with water that has been sitting outside in their drip tubing, but to avoid this, attach your anti-syphon to the beginning of your drip system.
Pressure Regulator
The pressure regulator is a critical component for ensuring safe, consistent water pressure within your drip system. Pressure regulators come in different PSI (pounds per square inch), though 15 PSI and 25-30 PSI are the most common. The average PSI for a spigot in our region falls between 50-70 PSI, which is too high for drip system components. The pressure regulator connects to the anti-syphon and forms the starting point for your system, protecting your drip tubing and emitters from leaking or breaking.
Drip Tubing & Fittings
Once you have your timer, anti-syphon, and pressure regulator connected, it is time to build your system. Drip tubing forms the skeleton of your system, getting the water where it needs to go through ½” or ¼” tubing. They can be cut to measure to fit specific spaces.
Compression adaptors are a type of fitting that converts the standard ¾” spigot or hose thread into ½” drip tubing or ¼” drip tubing. Connectors, tees, and elbows are additional types of fittings that attach to ½” drip tubing or ¼” drip tubing, which allow you to customize the shape of your overall system. You will need snug seals to keep your system from leaking, so getting your drip tubing into a fitting can be tricky. Soaking the end of the tubing in hot water to soften the plastic will help you work it into the fitting. When it cools, it will form a solid seal.
Emitters
Pre-punched drip tubing is ideal for creating lines or grids to water plants with small root systems such as groundcovers or vegetable starts. However, manually adding your drip emitters to your drip tubing with a hole punch allows you more control over your water output. It is important to use a hole punch specifically designed for a drip hose (rather than an improvised one) to ensure precise holes that will match your fittings and emitters. The hole punch by Raindrip also comes with hole plugs that you can use to reseal your drip tubing as needed.
Emitters are a range of components that convey water in different ways. Drippers release a steady amount of water at ½ gallon per hour, one gallon per hour, or two gallons per hour. These emitters are ideal for containers, vegetable beds, or plants with larger root balls. Bubblers act as small sprinklers. These emitters are best used on plants with shallow root systems, such as groundcovers, turf grass, or mass plantings of small annuals.
End clamps
Finally, it is time to close your system! End clamps are the simplest way to close your system by bending a drip tubing back on itself. End plugs are a more efficient component, as they also function as a water release valve at the end of your system. You can also create a looped circuit by using a tee-shaped fitting at the beginning of your circuit.
SETTING UP A DRIP SYSTEM
First, have a plan before purchasing your components and starting your setup. Measuring your space and sketching out a circuit is a great place to start to ensure you have the right length of tubing and the correct fittings to get water where you need it to go.
Thinking about the water needs of different plants will help you choose your emitters. For example, a container of annuals in the shade will likely need less water than a container of annuals in full sun; a raised bed can be irrigated by building a grid of pre-punched ¼” drip tubing; a single pot of strawberries might only need a single emitter while one water-loving hydrangea might need a loop with two or three emitters to ensure its entire root ball is getting sufficient water. If you aren’t sure, ask a Swansons employee about the water needs of different plants!
Water will always follow the path of least resistance. Your system can become less efficient if your circuit:
● is too long
● has too many emitters
● uses emitters that drip at different rates
● runs uphill, or against gravity (e.g. up a structure to hanging baskets)
These issues can be counteracted by creating a loop, using a tee-shaped fitting at the beginning of your circuit. A closed loop allows for relatively even pressure throughout the system. However, while a looped circuit will help even out the drip rate of your emitters, having too many emitters or emitters that drip at differing rates may still require you to run water through your system for a longer period of time to ensure all your plants are getting the correct amount of water. You may also consider installing a second, separate circuit that runs at a different time from your first circuit.
Once you have installed your components, it is time to test your system. There are countless factors that will impact your water output, including wind, temperature, soil composition, gravity, and water pressure, so monitoring your system is critical to ensure correct watering. After running your drip system for a set period of time, check to see how much water each of your emitters has released. You can do this by digging into the soil around your plants to see how far the water has percolated down through the soil, or by placing a small reservoir (such as a cat food or tuna can) under your emitters to get a more precise measurement. Once you have tested your system, you can bury your drip tubing and fittings under mulch to protect them from foot traffic and UV radiation. However, keep your emitters (including drippers) unburied to minimize the risk of blockages.
While the spring and autumn seasons in the maritime Northwest are typically cool and rainy, you may need to continue using your drip system to ensure your plants are getting enough water–especially those that are still becoming established in your landscape.
You can leave your drip system outside year-round, but be sure to disconnect it from your water source and allow the water to drip or drain out to avoid damage from freezing temperatures. Storing components like anti-syphons, pressure regulators, and emitters in a cool, dry place during the winter can prolong the lives of these products. In spring, test your system again to make sure all components are working properly, replacing or repairing any damaged pieces as needed.
As of this writing, Swansons carries drip irrigation components from Raindrip and Tempo, which are compatible with one another. These brands are ideal for watering containers, raised beds, and smaller garden areas. Mixing components from other drip systems is not recommended, as component sizing between brands varies slightly (even when marked as the same size), leading to fitting problems.
Drip irrigation is a fantastic watering method that is precise and efficient. Once you have set up and tested your system, it also will save you time and energy in keeping your plants watered when your garden is not receiving sufficient rainfall or while you are away from home. While this post is meant to demystify the dozens of drip irrigation components and address the most common issues with setup, every garden is unique.
If you have questions about components, need assistance sketching out your circuit, or are unsure about the watering needs of different plants, email us or visit the store. Our team is here to support you!
Tagged: drip irrigation, watering tools, watering, watering plants, watering guides