They recommend 80#/A of P and 40 of K. I would do that, and put 1+ ton of lime/A.

 

Plus 30-50lbs/acre of nitrogen to get started.

I would recommend talking with a local agronomist to get a blended fertilizer that gets you close.

 

They recommend 80#/A of P and 40 of K. I would do that, and put 1+ ton of lime/A.

Plus 30-50lbs/acre of nitrogen to get started.

I would recommend talking with a local agronomist to get a blended fertilizer that gets you close.

No one has educated him on how you arrived at these numbers and conclusions as he ask you to do.

 

I see their recommendations, but I don't know how to arrive at a certain mix and application rate of that mix.

My fertilizer plant is in the business of selling products and I'd like to know if they are at least in the ballpark with folks here that do know what should be done instead of selling me what they want to sell, they are know for this.

My field is only 12 acres and I'd like to get the ground in shape again.

Chris

 

I see their recommendations, but I don't know how to arrive at a certain mix and application rate of that mix.

My fertilizer plant is in the business of selling products and I'd like to know if they are at least in the ballpark with folks here that do know what should be done instead of selling me what they want to sell, they are know for this.

My field is only 12 acres and I'd like to get the ground in shape again.

Chris

I have the same issues. I usually submit the samples to my agronomist and he groups the fields and lets me know what to order. What I want to learn is how to take the sample and turn it into a usable number you would find on a bag.

 

Potash is 60% potassium, so to get 80# you will need 133# of potash.
The source of phosphorus I have to work with around here is diammonium phosphate (DAP), which is 18-46-0. To get your required 40# you will need 87# of DAP. This will also give you 15.6# of nitrogen.
I don't know how it works in your area, but around here lime is delivered in semi load lots, which is about 22 - 25 tons. That would be the perfect amount for you. Lime is spread separately and ideally should be tilled into the soil. Surface applied will take much longer to correct soil PH, and will only be effective in the top few inches.

 

The three numbers on a bag of fertilizer stand for nitrogen- phosphorus- potash. N-P-K.

So a 100 pound bag marked 10-10-10 would be 10 pounds of each and 70pounds of filler.

Common AG fertilizers in my area are Urea 46-0-0 and Muriate of Potash 0-0-60. Phosphorus is naturally very high in our local soils.

So if I ordered 100 lb of each, to be spread per acre by my farm store, From the 200lb of fertilizer I bought, I would get 46 lb of Nitrogen and 60 pounds of potash per acre.



Your soil sample recommended N(60)-P(80)-K(40)

So you could apply 150 lb of 46-0-0 = 60lb of N, plus 200lb of 0-46-0 =92lb of P, plus 66lb of 0-0-60= 40lb of K (potash).

So for 12 acres you would need 1800 lb of 46-0-0, 2400lb of 0-46-00, and 792lb of 0-0-60.

But remember, you’re farming, not making soup, so you can’t measure fertilizer by the spoon full. More than likely all the soil in your general area will require the same kinds of fertilizer so they will be available. I am fortunate that I can get my fertilizer custom mixed and spread to match my needs. And remember that the spreading process is not exact so you will get a little more or a little less on some acreage.

Also remember that the fertilizer recommendations are approximate, so you could put on a little more or a little less without causing a problem.

If you’re going to buy the fertilizer by the bag and spread it yourself you’re going to be limited by what kinds of mixes are available. For example if you spread 19-19-19.

400 pounds of 19-19-19 would give you:

76 pounds of N….good for the crop, 76 pounds of P close to recommendation, and 76 pounds of K, almost double the recommendation (which may or may not cause problems).

Welcome to the world of fertilizer calculations.

 

Not sure how much you know about Soil Samples, but as an agronomist I figured I would try and help you out. Nitrogen (N) is easily the most demanded nutrient that goes out the door. Nitrogen is essential for growth and yield, and Nitrogen Deficiency is usually represented by the crop turning a yellower shade of green. Nitrogen is also very mobile in the soil, Meaning it can "Leech/Leak" out over time especially in wet environments. Because of this, N recommendations are typically only made based on Crop Removal (Historical numbers showing what a crop typically removes from the soil in order to yield) for fields of Corn and Grass. To get a Nitrogen recommendation for any crop, just look up a crop removal calculator and you can configure it to show you "If you expect 4ton/acre yield, you need X pounds of N". Grass likes N, Alfalfa really doesn't. Your P&K are important for Grass, but not like they are for Alfalfa. Phosphorus and Potassium are also MacroNutrients like Nitrogen, but we can determine how much is necessary based off of soil samples as well as crop removal. Using soil samples allows us to see exactly where your levels are sitting. Are they High? Are they Low? If your P or K are high on the soil test, then we know we can cut back a little on the broadcast application. You NEVER want to knowingly go too low and "Mine/Strip" the nutrients or you'll just be digging yourself a hole. If your soil tests show you are seriously low on some nutrients, then maybe your Crop Advisor will recommend a "Build Blend" where every year you will fertilize for Crop Removal, plus some extra to get your numbers up as well as feed the crop. My recommendation for someone in your position: Grid Sample your field once every 4-6 years. Line it up so you soil sample, and Lime in the same year. If your nutrient levels are low, talk with your salesman to correct it with fertilizer. You can go online and read/teach yourself how many pounds of P&K it takes to increase nutrients by 1 part per million if you dont trust your salesman. If your nutrient levels are normal, find a fertilizer blend that you like and stick with it. As a salesman around Central/Southern MN, my go to blend would be something like a spring application of 100-40-60-15s. All blends are labeled in this fashion where your numbers are in order of Nitrogen, Phos, Potassium, Sulfur. So Per Acre I am recommending 100#N, 40#P, 60#K, and 15#s. You have to remember though, that your blend label is showing you "Actual Pounds" of nutrients, not pounds of fertilizer so we have to take it one step further to figure out your rate of actual fertilizer products like Urea, DAP, MAP, Potash, etc. So per acre you're gonna get 100-40-60-15s, but that really translates to:
Urea- 155lbs
Potash- 100lb
AMS-62.5lb
DAP-87lb
TOTAL RATE PER ACRE= 404pounds

We get there by knowing that the fertilizer UREA has an analysis of 46-0-0 which means 100 pounds of Urea only gives you 46 pounds of Actual Nitrogen. But something like DAP or MAP get tricky because technically we use them as Phosphorus sources, but they also contain a little Nitrogen that you have to account for. MAP=11-52-0 and DAP=18-46-0. So now, if we did 100# Urea and 100# MAP, you're going to end up with 57-52-0 per acre. And AMS is 21-0-0-24s.

I believe that's everything you should need to know to build a fertilizer rec on your own from start to finish. Like I said, you can build your Rx (Recommendation) using two different strategies. Crop Removal and Soil Test. Crop removal calculators can be found for any and all crops online, soil tests give you your Rx right at the bottom. So for you, I would recommend 100-80-40-15s OR 174# DAP, 62.5# AMS, 67# Potash, and 120# Urea. Like I said though, N is mobile in the soil so I would recommend waiting to do any of this till spring; Except the Lime, do the lime in the fall.

EDIT: Not to throw too much at you here, but if you wanted to manage your fertilizer even further I would recommend splitting your Nitrogen applications. you could do 60N in the spring and then: 40N after each cutting OR 60N after 2nd cutting OR if you're grazing do another 60N sometime early-mid June. Keep in mind that all of my advise has been learned from working in ND and MN so it may not be totally applicable where you're at.

 

Thanks, that explanation helps, and at the same time confused me a little, but I'll study up and learn as I go..

Thanks for everyone's input.

 

Trying to think how to simplify this further lol

So if you look at your test results, on the Left it shows your nutrient levels. If we look at your Potassium, its saying that CURRENTLY they are detecting 80 pounds worth of Actual K per acre and the bar is showing just passed "Medium".

Towards the middle where it says "Recommendation" its calling for 40 pounds of Actual K to be spread on your soil in order to get you Potassium to "Sufficient" levels. This is basically telling us that your lab thinks you should be at 120 pounds of Actual K, and youre at 80 currently. You need another 40 in order to be where they want you to be.

To figure out fertilizer spreading rates and to build a blend, we first need to know what products we're using, and what their analysis is. My coop uses Potash for all Potassium needs. Potash has a fertilizer analysis of 0-0-60. That means for every 100 pounds of Potash, you get 60 pounds of Actual K.

To spread 40 pounds of Actual K, we take Potash (0-0-60) and use

(Actual K wanted) / (Potash)

which is 40 / .6 = 66.667 lbs of Potash is required per acre in order to supply 40 pounds of Actual K, which will get your soil levels to 120 Actual K, which the lab says is Sufficient.

For your Phosphorus, the lab says you have 10 pounds Actual P per acre already. They are calling for an additional 80 pounds to be spread. Our coop mostly uses DAP (18-46-0) for our P needs. Notice how DAP has 18N AND 46P? we need to account for that extra N and remember it for later.

ActualP wanted / DAP

80 / .46 = 174lb DAP required per acre to supply 80P

174lb DAP ALSO brings (.18N from DAP) x (DAP rate) = .18N x 174lbs/A DAP = 31N

So we need 174lbs/Acre of DAP to get your Phosphorus, but as a by-product we are also getting 31N so in total 174lbs DAP = 31N 80P

I always like adding 15 pounds of Sulfur to my grass blends as Grass benefits well from Spring S, but thats optional. I use AMS which is 21-0-0-24s so you use the same math as DAP, remembering to account for that extra N later when it comes time to figure out N needed and Urea rate.

I always like saving the Nitrogen for the end since other products have some in it. Nitrogen is never really shown on soil sample test results since its mobile in the soil, and because we pretty much always base Nitrogen off of Crop Removal/Expected yield. For grass I pretty much always just use 100N as a lump sum application in spring, if you wanted to split apply and do some N later in season I would do 60N for both applications. To figure out our N:

ActualN wanted - ActualN already provided

100 - 32(DAP) - 13(AMS) = 55N still left to fulfill

ActualN left to fulfill / Urea (46-0-0)

55 / .46 = 120lb Urea required per acre

So in total we're getting 32N from DAP, 13N from AMS, and the last 55N from Urea.

If you didnt want to use any Sulfur, you would have a remainder of 68N needing to be fulfilled. 68N/ .46 = 148lb Urea required per acre.

 

That does help thank you very much.

I talked with the plant, he recommended a 10-26-20 or 12-26-20 blend for now, ( I gust drilled in more seed ) then in late February a 18-24-12 , both @ 300lbs per acre. I don't know what all is used for the blend but I'll ask Friday when I pick 2 tons up...

This field won't be harvested next year, I plan to give the Fescue at least a year to establish before anything is taken off, I don't cut hay any longer and I'd just as soon get my dirt in shape then if anyone wants the hay they will need to be willing to apply as the samples say to or it will remain a field I bush hog and admire...

Thanks again for the help...

 

Forgot these weren't Upper Midwest Forums and almost choked on my water reading that a coop told you they would apply fertilizer in Late February haha. Havent looked into Fescue as a cover crop at all but up here we use a lot of triticale, seems like its getting a lot of representation as the best for "Green Manure" and soil structure.

I was a bit worried when I saw how low of rates they recommended for NPK, but then I looked at your CEC on the soil results and it makes sense. CEC basically represents how well your soil can hold onto or retain the nutrients in the soil; Higher numbers are better at holding the nutrients, but take longer to "respond" to the fertilizer/dont absorb the nutrients as fast so it takes longer to see your nutrients climb. Sandier soils with lower CEC leak nutrients out easier so it makes sense that they'd rather do multiple small rate applications, because the sand would be able to use the nutrients right after application when you need them. We farm in a lot of heavy clay with a higher CEC so we do a lot of Fall fertilizer, with the intentions that the nutrients would be available in the spring and onward, and Spring applied fertilizer would have the intention of supplying nutrients throughout Mid Summer-Early Fall.

Without stepping on your land, I'd have to agree with their recommendation. Seems like a fitting plan.

 

Most call our dirt red clay, I guess it does have a bit of sandy stuff in it lol..

 

Hello, I received my soil test back and I'd like a little help with what mix to apply.

I drilled new Fescue seed a few weeks ago, no rain yet but at some point it'll rain.

I have lime to apply and that will be done in the next few weeks.

I would like you to help me with what mix and application rate, AND explain to me how to get the mix and application rate based on this sample... I don't understand how to come up with what and how much to apply per acre and I'd like to know...

Chris

View attachment 96605

A couple of thoughts-
why don’t you use your state land grant soil testing lab? Va Tech provides actual blended recommendations for fert to apply and they are not in the business of sell fertilizer or lime.
why are they recommending dolomitic lime when you mag is way higher than Ca? Should be using calcic lime, not dolomitic
if it were my field and I wanted it built back up, I’d be applying 150-170 #k2o and see where you are in a year. At your current level, 40# k2o is a drop in the bucket. Look up the amount of p & k removed per year with what yield you get. Then you have to put that on to stay even plus more to build up your field.
i typically apply 65# actual N through DAP + Urea in March and then again after first cutting. Soil tests call for more at 3Tpa yield but it will lodge most years before weather is conducive for making dry hay so I stick with the 65#