RichS Soil Test 2017 Front

[RichS]

Sampled at 4" from just my front yard - 4k sq.ft - sampled at about 10 different locations and mixed. (My 14k sf back yard always has very different results - I may test it later).

A Penn State analysis in Sept. 2014 said it was way low on P, K, so I've put 4lbs/year Lesco 14-14-14 since then (2lbs fall of '14, 4 lbs each of the last 2 years). I overseeded with TTTF in the fall, put down starter fertilizer, and it came in very nicely. The native grass is mostly rye.

Lawn is pretty well cared for - cut weekly during the season, unless it's growing really fast (usually 3-4 weeks/year), when I cut on Friday evening and then again Sunday evening, always <1/3 the height. I've had occasional Red Thread problems, but nothing severe. Weeds are pretty well controlled, with spot spraying as needed. I rarely irrigate, other than when laying seed - Mother Nature takes pretty good care of us, and I let it go dormant for a few weeks in the summer if that happens. I'm pretty active maintaining the lawn, so am willing to invest some time/$ to do what's needed.

I put down a first treatment of Lesco 0-0-7 0.1% Dimension yesterday, watered in overnight. About 4lbs/1k, with a 2nd application planned in 6-8 weeks (I'm in Lesco's Northern zone, but only 50 miles north of the Transition zone, so I rounded up the Northern recommendations a bit)

I have PSU results every 3 years back to '07, and a baseline from when I moved in, 1998, if those would be handy. Including one this spring (I send half of the mixed sample to each lab). Every test over the years has said low in K.

The pH was in the mid-5's when I originally moved in. I overshot and it was up to 7.4 in 2010 - I haven't limed since then (PSU says 6.9 this year).

https://richs.smugmug.com/Other/MiscTes ... -XNF8mp2/A

[andy10917]

A Penn State analysis in Sept. 2014 said it was way low on P, K, so I've put 4lbs/year Lesco 14-14-14 since then (2lbs fall of '14, 4 lbs each of the last 2 years).

4 lbs of 14-14-14 over what area? 4 lbs/K, the whole lawn, or what area? Your statement above doesn't allow us to calculate the amount applied...

[RichS]

4 pounds of product per thousand square feet of lawn surface area - one pound each in late May, early September, mid-October, and late November after a final cut. So about 30 pounds of 14-14-14 over my 4k s.f. front lawn at each application, four times a year.

I think I also put 1/4 pound/1k early April (so 7.5 lbs of 14-14-14 over 4k s.f.) last year as it had come in a bit slow/yellow the previous years. It greened up very nicely with that little kick.

[LoneRanger]

I'm confused.

[andy10917]

I got it.

[RichS]

by what?

30 pounds of 14-14-14 fertilizer contains 30 lbs * .14 = 4.2 lbs of each nutrient. 4.2 lbs of a nutrient spread over 4k square feet is 1.05 lbs/thousand square feet, for each nutrient (N, P, and K).

I applied this amount (30 pounds of fertilizer) four different times through the year, for a total of 4.2 lbs of each nutrient applied for the entire year. (I rounded 1.05 and 4.2 to 1 and 4)

If it helps, please just ignore all the info about the past.

[andy10917]

Almost everyone that tries their hand at reading soil tests asks me the same exact question: what are the threshold numbers that divide "needed" from "has enough". And everyone gets angry when I tell them that there aren't numbers like that - they think I'm holding out.

Your soil test gives few hints about your theme of "where is the Potassium going?" questions - if you look at single numbers. But it sings an Aria when you look at the numbers in combinations with context.

You have a soil with a TEC of almost 10 -- which would indicate a medium loam. But look at that OM%!! At 5.43, it's telling me that it's involved in the TEC number (lifting the TEC). Hint 1.

And then I see a 7.0 pH and a Ca:Mg profile that I wouldn't expect in your area. Hint 2.

Your comment about a pH overshoot to 7.4 in 2010, slowly falling to 6.9 or 7.0 in the past 7 years ties it together.

The TEC/OM says that the mineral part of your soil is probably sandier than the TEC would indicate. The soil may "leak" nutrients more than a TEC 10 soil, because of its structure.

The falling pH off an overshoot says that's probably happening - pH doesn't fall unless the elements that make it up are exiting stage right.

But wait, there's more!!

When you add the chemistry into the picture, the following comes out -- Calcium and Magnesium are falling out but the soil exchange sites actually prefer the cations: Calcium most preferred, then Magnesium and finally Potassium. You're adding the least preferred element and it's getting displaced by an abundant Calcium and Magnesium supply.

Stay on the 14-14-14 this year and I think we'll hit my Phosphorus target. Potassium, probably not. Apply at 7 lbs/K monthly until September (exclude July) and then switch to the Aggressive Fall Regimen. Late-Season Potassium has a potential to increase Snow Mold incidence, so I wouldn't roll the dice. With an Aggressive Fall Regimen, I have a feeling that slow-starts will go to the rear view mirror.

Iron is just below where I'd like to see it, but you're near the pH tipping point for Iron, so a few bags of Milorganite slipped in between balanced fertilizer apps wouldn't hurt.

In the micro's, it's Boron and Copper if you want to start that road this year - let me know.

[LoneRanger]

Now I understand. Your statement "4 pounds of product" was confusing me. I didn't realize you were referring to the actual NPK amounts.

[RichS]

Thanks for the thorough reply, especially the thought process and reasoning behind the recommendations - my engineering brain greatly appreciates getting to the answer as much as the answer ("show your work" was drilled into my head as an undergrad/grad student).

A few follow-ups (along with the standard advice I give new folks on my team - when I ask "why did you do this" or "why didn't you do this", it doesn't mean I disagree or have a better answer - I just want to understand the details):

When to start? Monthly applications starting April 1, and the 1st of the month going forward? I mowed this last weekend, mostly to suck up leaves, sticks, garbage, etc., from the winter, at the same height as my final cut last fall. I picked up about 1/4 of a normal cut, and soil temps are now in the low 50's, so the growth may just be starting.

If my math is right, this would result in about 9 lbs N/1k - (1lb * 5 months) + (1/2lb * 6 weeks) + 1lb. This is much higher than I've used in the past, so just want to be sure. I suspect I'll be cutting a lot - no worries about over-stressing the plants with lots of growth?

I'm up for B/Cu. If it's still the recommendation, I actually have 20Mule Borax in the closet from my daughter's science fair - apparently it doubles as a lawn boron source and a key ingredient in slime. And I assume this would meet the Milorganite recommendation, using it as a carrier.

Are micros something that need to be added annually/periodically as they leach/get absorbed, or once added they're permanent. Or "it depends" .

Any reason not SOP to tackle the Potassium? Doesn't react well with something else, too much at one time, or just not the right solution?

Thanks

[andy10917]

When to start? Monthly applications starting April 1, and the 1st of the month going forward? I mowed this last weekend, mostly to suck up leaves, sticks, garbage, etc., from the winter, at the same height as my final cut last fall. I picked up about 1/4 of a normal cut, and soil temps are now in the low 50's, so the growth may just be starting.

Many longer-term members saw your question here, rolled their eyes and knew exactly how I would respond. You're thinking about the calendar. Calendars are very good - the paper degrades well in the compost pile and that is where they belong. If you winterized in late Fall, the lawn may make it as late as the second half of May before it begins to show it needs a good shot. It's best to let it enter the Flush all by itself. Your optical receptors will tell you when the time has arrived - trust them.

If my math is right, this would result in about 9 lbs N/1k - (1lb * 5 months) + (1/2lb * 6 weeks) + 1lb. This is much higher than I've used in the past, so just want to be sure. I suspect I'll be cutting a lot - no worries about over-stressing the plants with lots of growth?

Quite the opposite. You are remineralizing the soil and encouraging dense, healthy growth that will long-term require fewer toxic herbicides and fungicides. Will you mow more? Probably - but we can discuss growth regulators that will almost pay for themselves if you want to. But leaching and run-off will be lesser problems as you learn to apply the stuff properly and in BALANCED amounts. Read about Liebig's Law of the Minimum (1828) for more info. Plants don't stress if they're not be forced to grow by Nitrogen in the absence of other nutrients.

I'm up for B/Cu. If it's still the recommendation, I actually have 20Mule Borax in the closet from my daughter's science fair - apparently it doubles as a lawn boron source and a key ingredient in slime. And I assume this would meet the Milorganite recommendation, using it as a carrier.

Boron is from the Mules, and Copper from Copper Sulfate (available at Amazon/EBAY). Buy a lb or two for every 8000 sq ft. Apply three tablespoons/K every 60 days, as specified in the Micronutrient Application Guide. Bo carryover applications into next year without a new soil test - teensy amounts are good and overapplications can be biocidal.

Any reason not SOP to tackle the Potassium? Doesn't react well with something else, too much at one time, or just not the right solution?

Cheaper and much easier to find for the gross work is the real answer. Depending on whether we reach we get to finer tweaking next year, we'll switch to the "good stuff". Balanced ferts are fewer applications when both P and K need work, and I hate to see people quit the regimens over the number of apps that need to be made.

[RichS]

Glad to hear that the process starts when the grass says it needs it - that makes sense to me.

Regarding stressing the plants, I think we are on the same page as I found and read the aggressive fall plan in detail. I've seen notes/research that adding N and forcing top growth can stress the plant or take away energy that could/should be stored, but I recall that this is in the context of summer heat stress and slowing growth in the fall, prepping for winter, storing up energy in the roots, etc. I think the pause in application in "July", which I read as whenever the lawn is under heat stress, and the late fall "Pause" addresses just what I was thinking.

I found the Micronutrient Guide, along with the Fall Plan - reading through all of those (being new here) is helping flesh out all the details.

I think I'm good to go as the weather warms. I've found sources for everything - local and Amazon - and the application guides look to be enough to guide me.

I may grab samples from the back this weekend and send them to the lab to see what they look like. I'll probably stick with something "basic" there - as it's 4x the size, I think the time/effort will focus on the front and see how it goes this year.

just for context, when you mention growth regulators to address mowing demands, are you referring to something like Proxy/Primo/Embark?

Thanks again.

[andy10917]

just for context, when you mention growth regulators to address mowing demands, are you referring to something like Proxy/Primo/Embark?

Yes sir.

[RichS]

A couple of follow-up questions-

20Mule and Copper Sulfate - 3 tablespoons of each, correct?

Is there any reason not to use standard fertilizer as the carrier for distribution? I'll use Millorganite in the front, per the instructions, but I have another 15K s.f. in back that I probably won't invest as much time/effort in (soil sample went to the lab today). I'll probably stick with just fert there - can 20Mule/Copper mix in with it using the same process (assuming the test says it's needed), or is there some interaction to avoid?

I looked at the price of 14-14-14 last year and my local big box stores have 10-10-10 and 12-12-12 much cheaper (and closer). I'd need to adjust the rates to 10 and 8 lbs/K, but any reason not to use them? There are 2 main differences:

- the 14-14-14 is slow release (70% N, 80% P and K), whereas the 10-10-10 and 12-12-12 are fast release. Any issues with using them - or splitting applications every 2 weeks instead of monthly?

- the 14-14-14 has other components - 4.7% S, .45% Fe, .45% Mn. I'll get Fe from the Millorganite - is there either a need for or an excess of Sulfer (or Mn) that would make this a better/worse choice?

Thanks

[andy10917]

We already got the micro's question answered above:

Boron is from the Mules, and Copper from Copper Sulfate (available at Amazon/EBAY). Buy a lb or two for every 8000 sq ft. Apply three tablespoons/K every 60 days, as specified in the Micronutrient Application Guide. Bo carryover applications into next year without a new soil test - teensy amounts are good and overapplications can be biocidal.

Is there any reason not to use standard fertilizer as the carrier for distribution? I'll use Millorganite in the front, per the instructions, but I have another 15K s.f. in back that I probably won't invest as much time/effort in (soil sample went to the lab today). I'll probably stick with just fert there - can 20Mule/Copper mix in with it using the same process (assuming the test says it's needed), or is there some interaction to avoid?

I dunno. If the fertilizer prills stick together with the technique I've used for spritzing the Milorganite, don't ask me what to do. I documented a way that is tested and works - anything else is at your own risk. I have no opinion.

the 14-14-14 is slow release (70% N, 80% P and K), whereas the 10-10-10 and 12-12-12 are fast release. Any issues with using them - or splitting applications every 2 weeks instead of monthly?

Nope. Why people buy slow-release is beyond me: paying 2X to 3X is for the lazy or to protect against stupidity.

the 14-14-14 has other components - 4.7% S, .45% Fe, .45% Mn. I'll get Fe from the Millorganite - is there either a need for or an excess of Sulfer (or Mn) that would make this a better/worse choice?

You are fine on Sulfur and somewhere between Ludicrous and Almost-a-Problem on Manganese.

[kbgfarmer]

Nope. Why people buy slow-release is beyond me: paying 2X to 3X is for the lazy or to protect against stupidity.

Correct me if I'm wrong but I reckon this is due to a combination of marketing (especially on the fertilizer bags talking about slow-feeding blah blah blah) and lot of university websites and other lawn sites stressing the need to use controlled release sources due to concern about stressing lawns and need for more frequent application. So I guess you're correct. They are reaching out to the lazy and stupid which unfortunately describes most of mankind.