I've had the soil station for over a year now, but finally got around to installing the 2nd, 3rd, and 4th, soil moisture and soil temp probes. It was a long, hot process, but I'm glad to have them installed. I trenched about 100 feet, and don't think I'll do that again anytime soon.
I finished this project so that I could accurately water my lawn here in Dallas where water is expensive, but also so I could water properly, by not putting out too much. Too much water makes the grass roots stay shallow, which in turn, hurts the plant during drought and periods of heat stress. I didn't bury them like a crop farmer would, but instead placed them 5" down, near the root zone, in four places in my yard. I bought some 18-8 sprinkler wire
, soldered the probe leads to that wire, then did a heat shrink over the connection. So far, all is working perfectly. I share this because even after a call to Davis, they couldn't tell me what type of wire to buy for the soil probes (surprise). They recommend shielded, but good luck finding that in an affordable option. I didn't run the wires near anything electrical, and all has worked well with the 18-8. If you do this in the future, I can recommend using what I used.
The nice thing about irrigation wire is that it's color coded, so all eight wires were easy to keep straight as to which one went to which probe. I essentially placed the soil station in the middle of the four points where the probes were buried, and then had four probes on one side (two temps and two moisture) run back to the station from one direction and the same from the other direction. 18-8 is 18 gauge wire with 8 strands inside it. Each probe has two leads, so two moisture and two temp gauges will work on one line of 18-8. By running two 18-8 wires into the soil station from two directions, I was able to have 8 probes (16 wires) all feed properly into the station.
Places like WU only broadcast the soil temp and moisture level from the #1 labeled probe, but my WeatherCat website lists all four. I had to use two graphs as WC only allows three inputs per graph. I wonder if there is a way to have the graphs use only 1 temp graph and 1 moisture graph instead of one graph per input? Anyway, the graphs can be found here on the Lawn section
and Graph section
of my website. A hot linked graphic below:
Finally, for the expense of the Soil station unit, I'm surprised at how cheap and low quality the connection points are. It has cheap, breakable plastic pins you push in to open the "teeth" that grab the wire. One broke on me in the process. It needs to utilize posts or screws, like even the cheapest irrigation controllers use, so it is more solid, and not prone to breaking. If you get a soil station, be very
careful about installing the wires into the unit. You've been warned.