Soils Analysis

Ridgerunner

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I just got my soils analysis results back. I took two different samples, one from the North of the garden and one from the South instead of getting one general sample over it all. I wanted to see if there was much difference in the results.

I move things all over from one season to the next. Some are mulched, some are not. I apply different fertilizers to different veggies, high nitrogen low P and K to corn, onions, garlic, and greens, a balanced fertilizer to certain things like tomatoes, peppers, and eggplant, and low nitrogen higher P and K fertilizer to beans and peas. A year and a half ago I emptied the chicken coop onto the northern part of the garden. I limed it all last fall. Over the years it’s gotten a lot of compost and a lot of mulch dug in to rot.

The only other soils analysis I have for this garden was taken in 2008. It’s really interesting how much many values have changed.

In ppm
........ North .... South...... 2008
P ........ 233 ...... 139 ...... 58
K ........ 247 ..... 141 ..... 118
Ca ...... 1539 .... 1446 ..... 995
Mg ...... 182..... 156 ..... 117
SO4-S .... 16 ...... 14 ...... 28
Zn ........ 9.2 ..... 8.6 ..... 7.4
Fe ........ 115 ..... 111 ..... 200
Mn ........ 155 ..... 154 ..... 316
Cu ........ 2.8 ...... 1.4 ..... 1.9
B .......... 0 ...... 0 ..... 0.4

pH ......... 6.9 .... 6.7 ...... 5.7
ECEC ........ 12 ..... 11 ....... 10

The oil is a silt loam for what that’s worth. That probably explains the Low ECEC. pH is high but that could be seasonal. Since I limed last fall I’m not too worried about that.

The only recommendations were a small amount of Nitrogen and some Potassium in the south end.

I’m no soils analysis expert but I’ll put this out there to see if a conversation gets started.

Sorry its hard to read. I don't know how to get this silly program to do columns

Hopefully that's easier to read.
 
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baymule

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I have never done a soil analysis. My garden is actually 18 beds all around the yard. I use horse manure compost, chicken and LOTS of leaves compost and mulch with grass clippings. Last year I grew corn for the first time in many years and it needed help, so I fed it bone meal and it perked right up and gave me a nice crop.

It looks like you have done a good job of improving your soil over the years. :thumbsup
 

Ridgerunner

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I've mainly got the "traditional" garden, whatever that is supposed to mean. I turned an area about 50' x 75' and started growing. I fenced it when the deer showed up.

It's not all that surprising how much difference there is in some of the areas. I use different fertilizers with different crops, mulch some and don't others. Phosphorus is above optimum so I'll cut back some on that in the fertilizer I use but I think the compost is contributing a lot to that too.

I've still got to do some studying and try to figure out what that low ECEC means I need to do. I think it means the ions can leech away pretty easily but I'm not sure if I need higher levels or that the ones that are there are more available to the plants. I think the high pH makes them more available too. Basically what I'm doing seems to be working pretty well so I'll pretty much stick to it, just a very few minor tweaks.
 

MontyJ

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The P isn't out of control, but is creeping up, so bears watching. Zn is higher than I would like to see it, what utensil did you use to take the samples? It could be contamination, or just a high level. It's not excessive though. Do you have any base saturation numbers? That's a better determination of how the soil is performing in relation to pH and CEC. Th pH looks great, especially after just liming last fall. B is low, but trying to correct it can sometimes prove to be disastrous. Overall, it looks to me like you are spot on. If I have time this evening, I can do some base saturation estimates based on your numbers.
The CEC is low, but is probably a function of the soil type. Heavier clay soils have a naturally high CEC because of the surface ares of the soil particles. Adding humus can increase the CEC, but you are often fighting a loosing battle as the finer particles stratify out over time. Double digging the soil can reintroduce those particles into the growing layer, but can also bring other things up with it that have also settled out.
 

Ridgerunner

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Good point. I used a metal trowel to collect those samples but it’s not galvanized. I don’t think it contaminated the samples. It’s a bit high but I’m not too worried about it. Still I'll use something different next time.

Base saturations
South…Total…78.2,…Ca…63.2,…Mg…11.4,…K…3.2,…Na…o.5
North…Total…79.8,…Ca…62.1,…Mg…12.2,…K…5.1,…Na…0.4

The calcium is a bit high but I don’t think excessively. I think that comes from using compost made from chicken poop. A lot of the calcium I feed to them for the egg shells is not absorbed by the chicken’s digestive system and goes on out the back end. That compost is probably pretty calcium rich. I certainly will not worry about a lack of calcium in my soil causing blossom end rot. It’s the water that causes that when I have a problem, not a lack of calcium.

It is a silt loam, with very little clay. That explains the low ECEC. There is a layer of clay way down but I turn by hand and usually don’t try to get too deep. It’s hard enough to walk in there when it’s wet as it is. I can easily sink down to my ankles after a rain. I think with the slightly high pH and low ECEC I’m doing OK.

Part of my problem interpreting this is that the Arkansas extension has a document online “Interpreting your Soils Analysis” but that document is not currently available. Perfect timing of course. I want to use their document if I can in case there are some things or tests they do differently, like using ECEC instead of CEC.

I don’t plan on changing anything I’m doing now unless you see something drastic and can convince me. I can be hardheaded sometimes but will listen. My concern in this is the phosphorus. It’s getting high. I’ll need to find Muriate of Potash and use that with a pure nitrogen fertilizer instead of my normal 13-13-13 to cut back on phosphorus build-up.
 

MontyJ

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Your base saturations do shed a little light on what's going on in your soil. H is taking up about 22% of your CEC sites, which seems a little strange to see considering a pH as high as yours. What stands out more is the low level of Mg. Did you lime with a calcitic lime? A dolomitic lime would bring the Mg levels more into balance with your Ca, and probably reduce the H, thereby increasing the total base saturation. Looking at your nutrient levels, Mg does appear low when compared to Ca, so that also indicates the use of a calcitic lime.

I wouldn't worry too much about the P levels. It readily leaches from the soil and should quickly return to normal after you stop using the balanced ferts. I'll bet you grow some nice peppers though ;) Your Ca is spot on in both nutrient levels and saturation. You are correct, only a lack of water would cause BER in that soil.

Frankly, I wouldn't mess with it much. There is nothing severely out of whack, other than the complete lack of B. If your not seeing any signs of Boron deficiency, I wouldn't worry about it right now. Your next application of compost will probably take care of that.

The Zn isn't crazy high, but could have been caused by a chrome plated spade, not just a galvanized one. In any event, it's not something I would worry about.
 

Ridgerunner

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Yes, the peppers have been nice the last couple of years.

I thought it was dolomitic but that bag is long gone. Thanks a lot for your help.
 

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