>>-3 weeks ago added 30lbs/1,000 sq ft pennington ast lime. Whoops, I didn't know this was 98% Calcium Carbonate and it's not supposed to be used at this high dose. Lawn isn't really yellowing too bad (yet)

Wait. :-) You did not kill the lawn, but we have to account for this. Some minor damage will probably result, and you seriously just bollixed your pH, though. The color should recover considerably by spring. On the up side, Pennington seems to have a larger sieve size, so it's a little slower than doing this would have been with Encap.

Your iron levels are very good, but you may want to apply a full dose of Milorganite at any time now to flow in a little more free iron (only some of which will make it to the grass, but we'll take what we can get). Repeat in October. The initially slightly acidic decay sequence of the Milo will also help (it goes neutral eventually).

Since you need boron, I'm scheduling a Milorganite drop for September 15th anyway.

>>Items on hand:

>>1) 20lbs potassium sulfate

Good, you're going to need it.

>>2) 12.5lb bag of Scotts 32-0-4 good old synthetic

Perfect for winterization at the end of the season when the grass starts growing but is still green.

>>3) Two 50lb bags soybean meal

This can be applied in September or October at 15 pounds per thousand to provide a great feeding for your lawn. It can go at the same time as the Milo if you want, or use the Milo instead and save this for the May 1st organic feeding. Given the whacked nature of the calcium levels at the moment, I'm thinking a little extra nitrogen would come in handy, but it isn't strictly necessary.

Overall, the results are very good. You had a shortage of calcium, but we're going to have to wait for the next test next year to see what stuck. A few things would benefit from adjustment to put you in the perfect groove for a lawn, but nothing that remains is severe.

Let's step by step this.

EC 8.9, 4.9: Well, that's a split personality. In front, it looks like mixed sand and silt, leaning toward silt. In back, sand with a bit of silt, predominately sand. On the up side, I don't think the back will be able to hold the calcium you dumped on it. The front will hold more.

pH 5.2, 5.8: Rather low out front, somewhat low in the back. Normally we'd fix this by adjusting the calcium, but... We ride it.

OM 8.7%, 9.0%: Excellent! There's no specific need to enhance this, but certainly no need to avoid organic matter. Mulch mowing and mowing your fall leaves is always a good idea. Feed organically if you like.

Sulfur 42, 30: Normal range. While the margin is a touch smaller than normal, it's not a problem.

Phosphorus 463, 415: Well over the top, but certainly not a problem. Still, I'd avoid phosphorus sources as you have tons of margin. Target in this case would be around 200--probably more like 250 with the current calcium glut, but that will drop back down over time and the calcium won't kick out the phosphorus.

Calcium 41, 59: Normally, I'd recommend about 12 pounds per thousand square feet total calcitic lime in the back, 20-ish out front (I'm not bothering to do the math here, just winging it). Your 30 pound app took care of this and then some, but fortunately in amounts that large you're going to lose a lot of it to leaching.

Magnesium 10.3%, 10.3%: (tapping teeth) I would have adjusted this fully before, but now I don't think I can do that so easily. Let's adjust this a bit in a pH-neutral manner to avoid sending the pH any higher. We use Epsom salt for that, available most cheaply at your local drug store in the bath or First Aid section. Recommendations below, and I delayed this a bit to give the calcium time to dissipate some. Magnesium is the central molecule in chlorophyll, and one of the reasons the grass paled out when you added the calcium--both are positively charged, and compete at the root zone to enter. Right now, calcium wins.

Potassium 1.4%, 2.1%: While the back looks fine, it's because there wasn't (previously) quite so much calcium. This just fell off the cliff in both zones. Your potassium sulfate is great for this, and again, I delayed application to dissipate the calcium a bit.

Sodium 1.2%, 1.7%: Completely normal, and there's no need to dispel this. The calcium you added probably kicked some of this, which is fine. Only the tiniest amounts are required.

Minor Elements: Everything except boron is perfect. I did mention iron above, although your levels are wonderful.

Boron 0.28, 0.26: Essentially a photo finish, and low in both cases. It really does require correction, and fortunately won't fight quite so much with the calcium as everything else does. I can shift this to September, but still want to give the calcium six full weeks to work in before stressing the soil with anything else. We use Milorganite as a carrier and 20 Mule Team Borax as the boron source. You can purchase 20 Mules at the grocery store in the laundry section. In a wheelbarrow or the like, dump the Milo. Spraying very, very lightly with water (I use a spray bottle like the kind people use to damp their clothes when they iron) will help the boron stick. Add the recommended amount of 20 Mule Team Borax and stir, spraying occasionally to get the stuff to stick to the Milo. Then apply over the recommended area. So if going for bag rate Milorganite (1 bag per 2,500 square feet), you'd add 10 tablespoons of 20 Mule Team Borax.

Recommendations:

September 15: Apply 4 tablespoons (not a misprint) per thousand square feet in Milorganite carrier.

October 1: Apply 1 pound per thousand square feet of Epsom salt to the front. Apply 2 pounds per thousand square feet of Epsom salt to the back.

October 15: Apply 2 pounds per thousand square feet of potassium sulfate to both the front and back.

April 1, 2016: Apply 1 pound of potassium sulfate per thousand square feet to the front only.

Wow thanks so much for taking a look at this! That'll teach me to apply lime off the bags label "If Ph is X.X apply XXlbs" I'll follow the schedule and keep you posted.

BTW, I see on the test the "Desired values" are different for front and back. Are they different because of the different OM and Exchange Capacities? Initially I thought the deficit was the exact amount of lbs required per acre to bring it within tolerance- but now I'm not sure how to read it...

File this one under "Oops." Excess calcium does lighten the lawn, and can cause some damage to your soil biology when added suddenly (your biology was previously tuned for a mildly acidic soil). Y'know what? It'll adjust, it'll just take some time. Calcium is never toxic, and people grow perfectly lovely (if somewhat pale to my eye) lawns in cracked calcitic limestone rock.

So figure three months or so until the bacteria fully repopulate with more neutral-tolerant ones. Same with the fungi. The worms barely noticed and didn't care.

Desired values are calculated off your exchange capacity--which does depend a lot on your organic matter levels. Higher levels of OM tend to lead to higher exchange capacities, since late-stage OM has a really high EC. You can make some inroads on low-EC soils by packing on the organic material, but there's no real reason to go to exceptional extremes or anything. Your organic matter levels are already exceptional.

>>Initially I thought the deficit was the exact amount of lbs required per acre to bring it within tolerance- but now I'm not sure how to read it...

That's correct...but... :-) Yeah, there's always a but.

One hundred percent of what you put down isn't going to bind in the region of soil we worry about (roughly, to about four inches where most of the feeder roots reside). Some will wash through, adhering to deeper soils. Those are essentially lost to your lawn, with exceptions.

What you add also isn't pure in terms of the element we want to put down...nor are the numbers on the bag necessarily correlating to the actual element amount.

Potassium sulfate, 0-0-50, would seem to be 50% potassium. It's not...it's 50% potash, which works out to 41.5% actual potassium by weight. Phosphorus is worse. Simple fertilizer grade monoammonium phosphate, 11-52-0, isn't 52% phosphorus, it's 52% phosphoric acid. Which works out to a scant 23% phosphorus by weight.

I'm also a fan of a little bit of extra potassium and tend to set the numbers a little higher than the suggested amount. Potassium enhances cold and heat tolerance, plus insect and disease tolerance. Good potassium levels, combined with proper winterization of your lawn and good feeding through fall mean that the lawn is much more likely to stay emerald green all winter. Which I often manage even here in Pennsylvania, on the border of the Appalachian mountains.

I set calcium levels a touch high as well. It leaches fairly easily, so it gives some margin against that, and grasses are fairly demanding when it comes to calcium. I could argue that it's the third most used soil-borne element (after nitrogen and potassium), although I wouldn't blink if you said it was fourth (after phosphorus as well). The argument can be made either way.

I'm definitely not a fan of excess magnesium and tend to keep it a touch on the low side. Higher magnesium levels lead, almost in a linear relationship, to tighter, more impenetrable soils that are difficult to dig. Nobody likes that, and it can happen almost as easily to pure sand as to clay. Magnesium is a distant fifth on the list of most-used soil-borne elements.

Deficit levels aren't given for minor elements because unless you know exactly what you're doing, fiddling can be rather risky. I gave you a boron recommendation, which is very firm--don't apply more than that, or apply any more without another soil test next year. Boron's optimal level is 0.7 PPM, or about 500 parts per billion more than you have.

If you imagine a billion seconds, that's right around 32 years. We're adjusting you by 500 seconds of that...or about 8 minutes. It's a very tiny change.

It gets worse in that at no point can any soil layer ever go much over optimal. Excess boron is toxic.

OK, I've totally been long-winded enough for one Friday evening....

Awesome thanks again!