I am having a hard time understanding this report. The only thing I do understand is the pH level is at 6.05. This is at the low end of the pH for grass. I don't understand why they don't recommend trying to raise it. You can add lime, but no need to go overboard. It takes a lot of lime just to raise the pH level a few tenths of point.

I'm a doofus. I missed the fact that the analysis was conducted on your 2/3 soil to 1/3 mushroom compost blend. Anyway, my comment about 0.0 ppm available nitrogen stands. I think it's a lab error. My comments about salinity also stand because we don't know the starting salinity of the compost or the soil. That being said, the final blend is 23% O.M. by dry weight, which is super high. If the mushroom compost was 1/3 of the final blend by volume, that would put you in the 7 to 8% organic range by dry weight if mixed with a mineral soil. And that's if the compost itself were high in organic material. (The analyses I looked at for the compost ranged from about 30 to 60% O.M. by dry weight). So, it would be a safe bet that your 4-way soil is probably around 15% O.M. by dry weight or a little higher. That means that it was probably about 50% to 60% organic material by volume and who the heck knows what that O.M. was. If it was raw wood chips, you would still have some available nitrogen in the analysis, but potentially not enough to balance carbon and it's feasible that you do indeed have a nitrogen draw issue. Or, if it has a heavy manure component, that could contribute to salts. (even a high quality greenwaste compost will often have a salinity level of 5 to 7 dS/m). Also consider that such a high amount of organic matter has the potential to hold too much water, especially if drainage isn't all that great at the bottom of the planters.

Spotty higher pH can happen if you got the soil off of one particular section of the pile...that happened to contain the old B horizon with some limestone in it! In my case, I got the old subsoil on my lot, so it just kind of stank all around. * You said you targeted our phosphorus level higher than your own lawn. Is this due to the pH difference or something else? Is phosphorus bound in the soil at higher pH's, and is our pH (7.1 - 7.3) high enough to cause that? pH. If you look at the availability of P by pH, it drops as pH rises above seven. You're not that far over, the binding isn't extreme, so I just boosted the numbers a little bit. Your standard is around 220, most people with slightly acidic pH would be around 200. In your case, I wouldn't blink at anything between 200 and 300. I never use my own soil as a standard, per se, for anybody else's. Mine have given in to some experimental stuff, plus I've over-enhanced the gardens to match the (extreme) density and (extraordinarily high) performance I demand they support. My current P levels in the garden push 1,000. * What kind of quality issues can we expect from the low phosphorus level until it's corrected? Thin, weak, sparse growth that gets sick and dies easily, discolors easily, grows poorly, and generally doesn't look at all good. Installed sod would tend to thin out and die back over the course of a year or so if it isn't corrected, resulting in a lot of thin patches and blank areas. N, P, and K are the big three and absolutely have to be there in the correct proportions (N we take care of on an as-needed basis). * It sounds like the Milorganite is great stuff, but I'm very sensitive to odors, so I don't think it's a good fit for our lawn. If we used ferrous sulfate instead (being careful to sweep it off the concrete), what rate and frequency would you recommend? I assume we don't need to worry about lowering the soil pH too much with the ferrous sulfate since the starting pH is above 7.0. I'd be comfortable with ferrous sulfate (monohydrate or pentahydrate, it doesn't matter) at 3 pounds per thousand square feet in April, early October, and perhaps early November if the weather's holding. Keep an eye on the pH in this case, though, as iron sulfate is about an eighth as acidifying as pure elemental sulfur and does NOT require digging in to work! Never use iron during hotter months or when the soil's going to freeze solid for winter within two or three weeks of use.

The testis a bit inconsistent in terms of pH versus ion concentrations, so I'm actually going to say that the test looks pretty good (I'm reading the ions not the roll-up numbers). I'd consider a Logan Labs test next time for a better read; I'm not directly familiar with VA Tech's testing processes.