As you start to read this, you probably think you’ve got me all figured out on this one. It’s likely that you think that I’m going to make a case for water conserving irrigation practices based on the weather that we’ve been experiencing over our “so-called” winter. While I certainly could go down that path, that’s now where I’m going to invest our time together this go-round.
I do have a few brief comments on this. Indeed, the shortage of snowfall this year and in other recent years has reminded us all that we DO live in a desert. As a society, we’ve learned to flourish here in the arid Mountain West, and we can easily fall under the spell of thinking that we live in place that is much more Midwestern, with plentiful water. Irrigation is a great thing that allows us to enjoy much more visually and agriculturally than we could otherwise. I’m all for creating great habitats for people, birds, wildlife and insects. If you’ve been to our place, you would know it would be hypocritical for me to say otherwise.
Having said that, I confess that my thinking is shifting bit by bit, and this “old dog” is learning some new tricks. I have quite a way to go, but there are changes happening in our yardscape as we encroach on the turf areas with deeply mulched beds that require much less water, even for ornamental varieties that require a good amount of water to flourish.
Last night, Matt Bunkall and Ron Haycock gave insights into their use of drip irrigation at the monthly Master Gardeners Free Public Class series. They’ve had great results, superior production and less weeds. Sure, I could make a case that the major appeal of low water use irrigation is water savings. But, I don’t need to. You already know that. In reality the appeal of what is commonly known as “drip irrigation” is much broader than just tubes with emitters. Said another way, drip irrigation is not a “one-trick pony” with only one thing going for it.
Like any living thing, plants have only so much “appetite” for nutrition and water. Too much water leads to problems like leaching away of soil nutrients, reduction of oxygen availability to the plant, and having too much at one time for the plant to make use of. The remainder either moves deeper into the soil beyond the reach of roots, or is evaporated off at the surface. So, putting smaller amounts of water, at the base of the plant or near its root line, on a consistent basis leads to a happier plant. Water is available as needed, without wet-dry cycling. Soil temps are kept cooler, and soil is softer for easier root development. Heck, you can even put in an inexpensive fertilizer injector system to allow the nutrients to dissolve in the water and be delivered right to the root system. Spiffy, huh?
That’s fine from the viewpoint of the plant, but what about the gardener? What do low water use irrigation systems have to offer you? PLENTY. First, even though there are a wide range of manufacturers and systems, they are all pretty straightforward and don’t require a lot of “ramp up” to learn how to plan or install. The components you’ll find in most systems are a water supply, main valve, pressure regulator, manifold (a main water trunk line that smaller lines are distributed from), tubing and emitters. The system is highly modular, meaning that the same types of devices are installed over and over. From there, the system is fine-tuned with timers, fertilizer injectors, zone valves, emitters with varying flow and delivery rates, and spacing of emitters depending on the crop being irrigated.
Because the system is simple, even “low-tech”, it’s also economical. Parts and kits are widely available from agricultural supply stores, big box home centers, Amazon, Ebay, and combination online and catalog suppliers like FarmTek (www.farmtek.com) and DripWorks (www.dripworks.com). Prices are very reasonable, and most of the components can be used multiple years. Parts that wear out are easily replaced without having to remove or replace a lot of adjacent elements.
Even more, you can also make your own system. My friend Brock Williams is a raised-bed vegetable gardener. He has two large beds and he uses his own drip irrigation system made entirely from PVC pipe components. The system is press-fit together (no glue) and runs at low pressure. He achieves this by using valves to turn down the volume in the lines. The whole network is tied to a zone on his main irrigation system for the rest of the yardscape. Brock purposely uses only dry-fitting to assemble his system because he can easily set up, service and stow his system. Even more, not having components glued together will automatically let him know if he is running the system at too high a pressure. Too much pressure will “blow open” a joint. Brock takes a decidedly low-tech, but highly effective path in creating emitters. They are simply holes drilled in the pipes, using a #57 steel twist drill bit (which is about 3/64th inch, or a little less than 1/16th inch), about 3-1/2” apart, or three per foot in his square-foot garden set up. This diameter, and quantity of holes, works quite well and keeps the plants amply hydrated. Brock uses the sprinkler controller manually and waters only when the soil starts to dry out. Last summer, that meant a watering schedule of three to four times a week, seven minutes at a time. If any of the holes plug up, he uses the same drill bit he drilled the holes with to clean them out. I love simple and Brock’s system is a perfect example of simple but elegant. Last year was his best garden yet, and his gives the lion’s share of the credit to his watering system.
Drip irrigation, either factory or homebuilt, is lightweight, and can be removed at the end of the season (in fact, I recommend it) for ease in plowing or tilling open field or amending raised beds. This means greater ease of crop rotation so that the right spacing is used for the planting. Because it is modular, the system is easily stored for the winter and then readily reassembled as needed the following year. I like anything I’m going to set up in the spring to be non-finicky, and these types of systems are a breeze.
I’d really be remiss if I didn’t point out one of the best things going for this system: weed suppression. If you want a good crop of weeds, simply cultivate deeply enough to bring fresh weed seed into the germination zone of the soil (about the top three-quarters of an inch) and then give it water regularly. In contrast, putting water right at the base of your plants greatly reduces the amount of water available to weeds in the open areas between the plants. If you are doing row gardening, this also means less soil compaction when you are cultivating or walking the rows. Drier soil stands up much better to people, equipment and overall gravity than moist soil does.
Effective watering is only one facet of successful ornamental and edible gardening. The importance of surrounding yourself with great resources and like-minded folks can’t be overstated. One such opportunity to get a lot of practical advice and meet some great people is coming up on Saturday, March 7 at the Tooele County Master Gardener’s Spring Expo. $5 registration begins at 9:30 a.m. with the first session beginning at 10 a.m. Workshops will be offered on a variety of subjects with a great general session at 1 p.m. Check out the “Bulletin Board” section under “Gardening” for more information. This is too good to pass up. Be sure to be there. I plan to be. But then, I’m on the schedule. If you want to learn how to grow grapes here in our area, be sure to come to my class that day. I’ll look forward to seeing you and passing on the knowledge my grapes have taught me.
Jay Cooper can be contacted at email@example.com, or you can visit his website at dirtfarmerjay.com for videos and articles on gardening, shop skills, culinary arts and landscaping.