Irrigation System for the home and garden
February 18, 2021
I don't know about you but I'm getting the itch to get outside and play in the dirt. I have a lot of projects planned for this year and some of them require an irrigation system to be installed. We've had plenty of rose bushes, honeysuckle, trees and other plants that have spent their entire life fending for themselves. My New Year's resolution is to be more involved in the yard and taking care of the plants that I've ignored for so many years.
My first major project was actually started last year. We've never had irrigation set up for any of the outlying flower beds so I started laying out a basic irrigation system, really out of necessity. If I'm going to take on more of the work in the yard, I need to use every time saving method I can find. The primary way to save time for me is to have an irrigation system set up so that I can turn on the water and send it to multiple locations at the same time. Hauling hoses all over the yard then putting them away would cost me five to ten hours each week. So I've decided to install multiple irrigation systems.
The first system is in the flower beds. The flowers and plants in these beds are pretty thick so even when I watered the lawn with an overhead spray these plants didn't get as much water as they need to thrive. The lawn is the only place I'll use an overhead watering system and that's only because there is such a large are to cover and a drip system or soaker system would be ineffective. An overhead spray system will lose up to 40% of the water to evaporation in the summer. Overhead watering is indiscriminate and the water goes everywhere but not necessarily where it needs to be. Having moisture dripping down through the foliage can cause other problems if your plants have dense foliage or are tightly spaced. When air is unable to move through the foliage and dry it out after watering you set yourself up for mold and other diseases to affect your plants.
The answer is an irrigation system that puts the water right at the roots where it will do the most good. In my flower beds I use a soaker system. The nice thing about soaker hose is that it releases water through micropores all over the hose. Most are a half inch to five eights of an inch in diameter so water placement is localized. I weave the soaker hose throughout the flower bed so that it covers the entire bed. The hose lays directly on the ground so water is placed right at the root and does not soak the foliage. That eliminates dampness in the foliage and robs disease organisms of the environment they need to thrive and multiply. I can hook up one hose and water the entire flower bed while I'm doing something else. By putting the hose on a timer you can even set the length of time you want the water to run. There are a couple of drawbacks to a soaker system to consider. The first is that they don't last very long before they develop leaks or break. Soakers that are in the sun may last three years before they have to be replaced, if you're lucky. If they are protected from the sun and never moved you can get a longer life. Mine in the flower beds have been in for about ten years and are still good. Another consideration is that they do clog from dust and other debris. You need to keep a close eye on them to make sure they are still effective.
My favorite irrigation system, though, is a drip system. It is the most versatile system I've found and lasts a long time. I put my first drip system on our windbreak trees 20 years ago in 2000. The only problems I've had with that system has been a lawnmower. I'm glad it's easy to repair. Primarily drip systems involve either drip tubing or drip tape. Both have a purpose and both work well. Drip tubing comes in multiple sizes and can be perforated or non-perforated. Again, different purposes.
Drip tape is primarily used in vegetable gardens where plantings are linear, planted in rows. Drip tape is not flexible when pressurized and cannot be made to turn a corner. Making a turn isn't difficult but does require adding fittings such as elbows to change direction. It is thin walled so it requires the use if a pressure reducer to keep it from bursting. Most wells have a pressure of 40-60 psi. City water is somewhat less. Drip tape can tolerate a maximum of 15 psi. Reducers are cheap and are carried by the same company that carries the tape. Drip tape can be buried just under the ground for even less evaporation. It comes with emitters at 4 inch to 12 inch spacing. The spacing is a great help when it comes time to set your bedding plants in the garden. Just set the plant beside an emitter and each plant will have an emitter dedicated to it. Since the water pattern is about six inches around the emitter I'll often plant on each side of the tape and save space. Drip tape has a two year warranty but will last a lot longer with reasonable care. Repairs are difficult, though, unless you use a coupler. Quick connect fittings are available and makes setting the system up easy and quick.
Drip tubing is a better product when curves will be in the system since it bends in all directions. It comes in perforated and non-perforated types. I use the perforated type when I want general watering or I'm planting at specified intervals. The non-perforated is best for long runs without plants or for irregular plantings. I'll use quarter inch perforated tubing or drip emitters to place the water where I want it. Multiple types of emitters and drippers can be used in the same system. Drippers are best when you want the water in a specific location. You can place the dripper at the end of a quarter inch non-perforated tube and place it exactly where you want it. I've started using the quarter inch perforated tube when I want to cover a larger area with more general watering, such as my lilacs, or I'll wrap the tubing around a plant to surround it with water. Drip tubing comes in a variety of diameters. Larger diameters carry more water for plants, like trees, that need more water. In some locations I've buried the tubing (to avoid the lawnmower) and in others I've left it above ground and staked it down tightly so it doesn't pucker up. Drip tubing is pretty resistant to freezing and breaking in the winter but it does expand and contract with temperature changes. Valves can help shut off sections of the system to increase water pressure and improve function. I use a lot of valves so that I have only one master line that connect to the hydrant and different segments of the garden can be irrigated separately.
All of the systems can be used with a hard PVC component if you prefer to go that direction. PVC will deteriorate if it's left out in the sun, though. Tubing is a lot easier to use and lasts longer.
Irrigation systems can be as simple or as complex as you desire. If you have any questions about irrigation system design or other horticulture matters ask a Master Gardener. It's what we do. You'll be able to talk to us in person at our annual plant sale on May 8th at the Archer Event Center. Happy gardening!