This irrigation stuff may be old news to Southern Californians, but we must remember that there are places where it rains, where gardens don't have in-ground sprinkler systems. Yeah, I know. Amazing. In some places, it rains in July. No, really!
I took the cover off the water meter at the street, and recorded the numbers before and after running each zone. That gave me the amount of water used for each zone. The water meter measures in CFs: cubic feet. One cubic foot of water is 7.48 gallons.
Getting to know you, Mr. Water Meter, getting to know all about youuuuu...
Some of the water is going here:
And some of it's going here:
Where we don't want it is here:
I got valuable information doing that tedious work, though wandering through the garden taking pictures of flowers while each zone ran more than made up for the tedium. I now know exactly where to cut. While I was at it, I was able to note indoor use: we're at fify gallons per person per day, which is fairly resonable. Go "navy" showers! That fifty gallons includes two loads of laundry--not something we do every day. The laundry water will soon go into the garden on a regular basis.
The Agave zone along the driveway uses one cubic foot, about 7.5 gallons. There are nine Agaves, so each Agave gets a little over two quarts of water. I can run that zone once a week and have very happy Agaves.
Plants are not the enemy!
The rose zone around the (empty) fountain take 1.67 cf, twelve and a half gallons. There are ten roses in that zone, so they are getting about 1.25 gallons each per irrigation run. In very hot weather, a rose needs about five gallons of water a week. In moderate summer weather, maybe half that. So I need to run that zone twice a week most of the summer, and more only when it is super hot.
Recording all twenty four zones, it became clear that a few of the zones, drip included, are using most of the water and getting too much for the plants--now I know which ones they are. I'll work on those first and get my 36% reduction. I will, I will.
Knowledge is power, but blue is beautiful:
Sprinkler problems: leaks, overspray, blockage of spray by the plant closest to the spray head. That's what I ran into here: the single Aeonium I planted became a large clump, and it was blocking the water to the rest of the area, keeping 90% for itself. The sprinkler was also leaking a little bit, which, while not a significant amount (a few ounces), looks wasteful. Because the sprinkler head was right next to the curb (pink X), it was not possible to keep spray from hitting the concrete and asphalt, so overspray was another issue. For now, I capped the sprinkler head off. Where it really belongs is where the blue "X" is.
Talk about tedious work...
Sprinkler location is a real problem. They are usually always placed at the edges of an area, right next to pavement; thus preventing pavement from getting wet is always an issue. Putting them 6 or 12" in from pavement can prevent some waste, but who actually does that?
I'd really rather be thinking about Dahlias
I very vaguely remember my Dad installing sprinklers right in the middle of the lawns at my childhood home. Edges of our lawns were dry, but there was no waste. The issue he ran into was the mower hitting the sprinkler heads, and little knees falling and hitting sprinkler heads, perhaps. Mower, bad. Little knee, aw, it will heal. Quit crying. Go get a band-aid from Mom.
Running zones 8 and 9, a Towhee kept peeping at me as I walked by a rose near the gate. Investigated...well will you look at that!
The main problem with drip systems is clogging due to hard water, and to a lesser extent, tubes cut by rodent teeth or trimmers.
Drip irrigation is not perfect; one must be alert for clogging, and sharp-eyed to see a thirsty plant or an overly happy one. In lawns, roots can invade and clog the tubing.
No clogging here:
The Netafim product I now prefer (no, they ain't paying me) recommends some kind of chemical application if drip systems are used under lawns. There's always something.