Soil test October 2003 A&L Western Agricultural Labs, Modesto, CA pH 7.5 Organic matter 2.3% (low) Nitrogen 116 ppm (very high) Phosphorus 121 ppm (very high) Potassium 911 ppm (high) Magnesium 499 ppm (medium) Calcium 3118 ppm (medium) Sodium 176 ppm (medium-low) Sulfur 495 ppm (very high) Zinc 3.3 ppm (medium-high) Cation Saturation Potassium 10.2% Magnesium 18.0% Calcium 68.4% Sodium 3.4% CEC 22.8 meq/100g Ece 6.3 dS/m
Good? Well I'm not really lacking in too many things. Bad... pH is still high at 7.5 but this is better than 7.8 two years ago. Organic matter is 2.3%, low but this is up from "imperceptible" at the last test. The potassium and magnesium are too high, or perhaps the calcium is too low. I'll continue to work on these numbers.
UGLY! You almost don't see it, but look at the last number, "Ece". This is a measure of salinity of the soil. After I got my test results, I posted them to the Mallorn list and quickly received a spreadsheet of test results. Of the 75 or so that reported a number for salinity, mine was the absolute highest!
I've heard that a number below 1 is good, and above 2 is quite bad. As you can see, mine is 6.3! A few reasonings... There is a septic drain field that runs across my lawn and into the garden. I noticed late last season that my lawn and garden in the areas near the drain field weren't doing well. Of the four samples taken, I think two of them could have been affected by the drain field.
I also live in a desert. Annual rainfall is only about 12 inches, and over the last four years we've had, oh, about half that. I also have a bad habit of watering frequently but not deeply. Finally, I've been told that some fertilizers leave too many salts in the soil. I've got to avoid them. Maybe, I've found a major problem. If I can water the soil really deeply, I might be able to improve things.