My compost is high in P and K with a Mehlich 3 soil test.

6 years ago

Hi, this is my first post on this forum and it looks like a good amount of people are composting. I might be in the right place then!!! I started composting in 2016 but my plants were always showing signs of stress, so I started testing my soil. All of the numbers looked great except for Phosphorus and Potassium, they were sky high. I mean like 10x the amount.

Here is what I was using for compost: Rabbit bedding, oak leaves, grass clippings, rock dust, egg shells, kelp, and fish meal... I started to read about leaf compost more specifically and I now understand that leaves can be used for trace elements and it is high in P and K. I also read that rabbit manure has 2x the amount of P and K compared to other manures like horse, cow, and chicken. Maybe, I am getting more P and K from the leaves and manure than I realized? I am starting to think that I don't need to add dry amendments to my compost.

I guess that I am here to confirm that rabbit manure and leaf compost will test high for P and K. More importantly, how can I make this compost usable, because I have a nice system going. I made a worm bin out of plastic pallets and I put a screen between each stall so that I can have a side-migrating bin.

I also have a 8'x8' concrete slab that I use for composting. I got a Geo Bin to collect grass clippings while the compost on the slab finishes. Here is some steamy grass clippings, I just turned the pile and I could feel the heat... Here is the big question though, why is it bare next to my compost? I thought that I was going to have to fight to keep vegetation away...

In the summer, I get both composting worms and black soldier fly larvae. The BSF ravage the compost!

Featured Answer

armoured

6 years ago

Just a question or two for clarification: did you test the soil or the compost? Where is this soil, in a vegetable or flower bed, or what exactly are you using it for? How is stuff growing there (that's what matters)?

And since wherever this soil is seems to have enough of almost everything, can you just spread the finished compost somewhere else? Like near the trees and bushes you have there (or give it away or whatever), at least for some time until you see how the situation develops.

Other specific suggestion: I'd say the results show you have no need for any specific additives or dry stuff like you've been doing.

Comments (43)

dustin2100
Original Author
6 years ago
This year, I didn't use any dry amendments to mix my worm bin. I did use liming agents like basalt, glacial rock dust, and oyster shell flour. The base of my mix is oak leaves and rabbit bedding. For the rabbit bedding I usually get one bale of straw and one bale of alfalfa hay. Plus, the rabbit feed is alfalfa pellets. What I do differently is feed the veggie scraps to the rabbits and the manure to the worms, so I really don't have a lot of food scraps in the bin. Some, but not much.

Anyways, I cannot find the copy of my compost soil test. I did have some soil tested that came from an "Organic" store that was supposed to be a premium mix, but the test results came back no better than my compost. The mix from the organic store was lacking most of the trace minerals and was still too high in P and K. I am guessing that high P and K is more of problem than I realized! The chart does not go high enough to show the amount of P and K that there is, 10x too much!!! Anyways, I can't build a good soil and I cannot buy one either. At least my compost had trace minerals and was only toxic in P and K, the "Organic Store" blend was too high in several areas.
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gardengal48 (PNW Z8/9)
6 years ago
Generally, compost is not tested for NPK. First, it is a soil amendment, not a fertilizer, so knowing the NPK is of minimal value. And compost is not very finished....even when you think it is :-) It will continue to break down and decompose and whatever nutrients it contains will be dissipated or leached and/or evened out. It is never a very high source of nutrients anyway....typically at most it will test out as 1-1-1 but the exact numbers will depend on what ingredients were used to make the compost and how "finished" it might be.

Very few natural materials will be 'too high' in P or K - rabbit manure is around 2.4-1.5-0.6. Oak leaves are 0.8-0.35-0.2. Grass clippings have a much higher K value (1.2). And fish meal has a very high P value compared to other compost materials (7.0).
toxcrusadr
6 years ago
last modified: 6 years ago
Fish meal you could definitely leave out of the compost, it's more of a fertilizer. As for the rock dusts, do you know you need them? You mentioned 'liming', so what is your soil (not compost) pH? Always know that before you add lime. And a good compost will offer all the trace minerals your plants need, so rock dust is not really needed for that (IMHO).

You mentioned steamy grass clippings. Always mix those with browns immediately upon harvest to prevent loss of N through outgassing of ammonia. I prefer to leave them on the lawn, but in the spring I harvest some to mix with the remaining fall leaves I didn't use for other purposes.
toxcrusadr
6 years ago
Also, as has been mentioned, the soil tests and their recommended ranges should apply to soil, not to amendments, compost, fertilizer, etc. Normally you wouldn't be growing in 100% compost, it's supposed to blended into soil. So it is not surprising to see test results exceeding what is recommended for soil.

Rather than spending money testing amendments, add them to your soil, give it some time to be incorporated (a season at least) and then test the soil to see where you're at.

The best way to give the soil a balanced diet is to make compost using a variety of materials, which you are doing, or if you're buying, use different products if you can. The bottom line, though, is that ANY compost is better than no compost at all, so don't fret over it too much. :-D
armoured
6 years ago
To reiterate what I meant by my question above:soil test results from testing compost will make no sense. If that was just a test of compost, don't worry about it.
Whassisname
6 years ago
last modified: 6 years ago
Your most everything is high. Sodium, salts, nitrate, sulfur etc.

That’s a very comprehensive and expensive soil test. You say it was done on a store bought soil? Values are not usually that high unless there is a sampling error like a piece of raw fertilizer or a chunk of manure was in the sample. Otherwise you might want to avoid that product.
dustin2100
Original Author
6 years ago
My problem is that I was using this for a raised bed and I didn't dilute it with soil or anything. I keep getting plants that fade yellow and show signs of Mg deficiency but I am dealing with a toxicity issue instead. Nothing was looking good at all and that is why I started testing my soil. I tested the soil this time before I added it to the raised beds, it was a pain to dig the soil back out.

I thought about mixing my compost with peat moss or something to dilute it and I might use some of the soil for container plants too. Thanks for the replies!
dustin2100
Original Author
6 years ago
From what I understood, compost can be used without being diluted. I am starting to question this thought though. I heard that leaf compost is a sustainable replacement for peat moss. Which led me to believe that it didn't need to be diluted.

I started to read more about the different soil tests and I don't think that I picked the best test. The Mehclich 3 test will show the total ppm of every element and does not account for nutrient lock-out. This is important because I just found out that phosphorus has a low availability in the soil. Just because it is there does not mean that it is in a usable form, so that might not be the best test for P. Potassium on the other hand. I read that K in excess can lock-out Mg and trace elements like zinc. Last year, my plants looked like Mg and zinc deficiency, but I am thinking that it was the excess K that was causing the problem. Another problem with the Mehlich 3 test is that the test is only accurate on soil with a Ph lower than 7.2. The Ph of my compost was 7.3...

After reading and understanding the different soil tests a little better, I found the "Soil Savvy" test. This test is different because it will show what is available(soluble) to the roots and not just the total amount present... I just got the test kit in the mail today. This kit is different because they send you a container that has resin and liquid that you add a scoop(provided) of soil and let it dissolve in the container. The kit comes with pre-paid postage and lab costs and the soil needs to sit for 5 days before they test it. It was $30 for the kit and there are no hidden fees is what I am saying, I was confused about this when I first looked at the kit.

https://unibestinc.com/industries/lawn-garden.html?gclid=Cj0KCQiA5t7UBRDaARIsAOreQtgRaxGl6lcUuf1VKBcFsbFkeX-P0jkX-NPbj9rs2RAgxUOP4h1rjxkaAgyEEALw_wcB

Anyways, I am moving on from my previous composts and test results because I have a new batch of compost that will be ready very soon. I have rabbit manure that has been aged since Apr 2016 and it has been in my worm bin, I never added any amendments to it either.
dustin2100
Original Author
6 years ago
I am looking at getting a loan and setting up a nice greenhouse, but I want to be able to make good soil before I get too invested. I am a disabled veteran and I don't have a job, but I do get paid about $52k/yr in disability and I wanted to make gardening a big part of my life! I am to the point that I realized how unhealthy my diet has became and I am trying to change that. I am getting fat enough that my knees and feet are telling me to loose weight. I love veggie soup and I make a big batch and jar it for the fridge. I would be very proud if I was able to make soup from my garden, herbs included.

I live in Oklahoma (Go Thunder!) and our soil is sandy loam with high amounts of iron and a low Ph. I have been looking at what veggies do well in Okla, but I would also like to have a raised bed for plants that don't like the Okie soil so much. For instance, blueberries are supposed to thrive here because of the acidic soil... I am getting a ground sample to send in with my compost sample.
glib
6 years ago
in a nutshell: too much compost and/or fertilizer was used. If you stop adding compost, use cover crops in the resting season instead, and keep eating the products of your garden, over time the value will come down to optimal levels. it is not difficult to stop adding stuff (with the exception of nitrogen). It is less work.
toxcrusadr
6 years ago
last modified: 6 years ago
Sorry to hear you had trouble with plants. It could have been pH, insufficiently composted organic matter, soggy and boggy and anaerobic when wet due to no mineral soil added, or just too rich in nutrients. After rereading the thread, I finally understand (I hope) what has happened: You filled raised beds with compost, plants did not do well, you dug it out and you want to replace it with compost you've tested.

The compost composition is not your problem. Your problem is trying to grow in 100% organic matter. You probably didn't need to dig it out and replace it, you probably just need to add some mineral soil to have a balanced mix. Not peat moss or leaf compost, but soil. You're going to have trouble growing in 100% organic matter no matter what it is. It's too much of a good thing.

BTW, the fact that the 'premium mix' from the store did not test any better than your homemade compost is not surprising at all. Home made compost with a variety of ingredients typically tests higher in everything than store bought. :-D
dustin2100
Original Author
6 years ago
I sent off the test samples today. One from my rabbit manure worm bin and one from the ground. The ground is sandy loam but it is red and I expect it to be very high in iron. I understand that the ground is red because the iron will rust, so there must be a lot of iron...

Here is the "Soil Savvy" test kit. The resin is supposed to absorb nutrients much like the roots will. This is supposed to be the closest thing that you can get to a plant tissue test.
dustin2100
Original Author
6 years ago
I think that you are right about using too much compost. My lawn usually does really well when I spot fix it with compost, so hopefully my ground soil and compost work well together.

I also wanted to use some compost for container gardening. I just found out that there is a separate section just for containers, but what would I mix that would keep that pots from being too heavy? I thought that pure leaf compost was supposed to replace peat moss, but I am confused about the whole thing. I really wanted to take a sustainable approach to this.
theparsley
6 years ago
You wouldn't grow things in pure peat moss, either. It's a component of many container mixes, but as already mentioned above, 100% organic matter is not an appropriate growing medium all by itself.
gardengal48 (PNW Z8/9)
6 years ago
Container gardening and the soil mix best recommended for that purpose is an entirely different set of conditions that have nothing to do with either ground soil or compost!! It is rather tricky to be a successful container gardener and follow sustainable practices, unfortunately......the two are not necessarily very compatible.

To be perfectly honest, I am rather perplexed about your practices and what precisely you are trying to accomplish. Compost is not a fertilizer nor a soil substitute - it is used as a soil amendment, to lighten or loosen a heavy or poorly draining soil and to add organic matter and increase water and nutrient retention in a very sandy soil.
dustin2100
Original Author
6 years ago
I don't have any education in gardening, but I wanted to make a change in my life starting with my diet. I have a few different projects going and I do feel like I am all over the place, but I do put hard work into gardening. To be honest, I am probably clueless in a big way but I do read books.

I bought a house with 2 1/2 acres that is heavily wooded. I started a couple of hugelkultur beds about 3yrs ago and I planned on making more raised beds later this year, probably regular raised beds this time. In the mean time, I was hoping to use large pots to grow some squash, strawberries, and a couple of other things. Also, my dad lives very close to me and he has a regular type garden that is just plain dirt. He gave up on keeping up with a garden this year, but I told him that I would come and help him. He never added fertilizer, so it should not be very tricky after we get the soil test results back. Anyways, the biggest garden is probably at my dad's house... So far, I spent about 3 days chipping leaves and the garden has about 3'' of oak leaf mulch now. I am holding off on adding compost until everything is tested.

Last year, all of my squash that was in containers got white powder mildew. They were also in a spot that didn't get full sun. It was a hard decision because summer temps can get well above 100F and stay there all of July and Aug.

I notice that I have an abundance of bees around here! I am considering clearing out some of the trees so that I can replace them with fruit trees and garden space. I hate the idea of cutting down living trees, but I think that I will feel better about it after I have workable land. The trees are kind of smothering my property and I don't have a lot of options for gardening spots. I realized that one of my hugelkultur beds is in the shade and I am tired of making mistakes like that.
perennialfan275
6 years ago
Gardengal I've heard that too much phosphorus can actually be bad for your soil, and most soils have plenty of phosphorus anyways so there really is no need to add more. Would you agree with this? Having said this, shouldn't we try to make sure our compost contains as little as possible? Phosphorus pollution is a serious issue, and especially if I'm growing edibles I want to make sure my soil contains as little of it as possible (unless you have one of the rare soils deficient in it).
dustin2100 thanked perennialfan275
floral_uk z.8/9 SW UK
6 years ago
Dustin, you are putting a great deal of time and effort, and potentially money, into your gardening. But I am wondering if you are perhaps vastly overthinking it? Have you tried simply picking an open sunny spot on your property and digging an old fashioned garden bed direct into the ground? This is about the simplest and cheapest way to begin gardening and it seems to work for your Dad. You say you have sandy loam. I'd love to have soil like that. You could use your compost as a mulch. I would hesitate to take out a loan for a greenhouse until you've got the basics of cultivation, seed sowing, weeding and watering under your belt. Learn to bake a basic muffin before you try to open a top end patisserie.
wayne_5 zone 6a Central Indiana
6 years ago
I really like what floral posted.

dustin, Start less hi-tech. Start more basic. If you have an open area away from shade, roots, and a drainage field, mix your good compost into the soil through the upper 10 inches....learn from there.
gardengal48 (PNW Z8/9)
6 years ago
perennialfan, that is not an issue that has a simple answer. Yes, an excess of ANY plant nutrient can be harmful to plant growth. But the phosphorus contribution from any 'finished' compost should be quite low - as I stated early on in this thread, a decent finished compost should test out to an NPK of about 1-1-1. That will differ some based on ingredients that went into the compost but it is still unlikely to be a very high number. And the P in compost is generally not readily available to plants anyway, as it is in its organic forum and needs to be mineralized first. And even after mineralization occurs, the inorganic P tends to be bound to other elements and is relatively stable. UMass did a study on compost use and soil fertility and had this conclusion: "Some studies where plants have been grown with compost as the sole source of fertility added have shown phosphorus deficiency more readily than nitrogen or potassium deficiencies. Generally, farmers should consider that compost is too low in phosphorus to consider use of compost in short-term fertilization of crops and should provide an additional source of phosphorus to ensure adequate crop nutrition." So it is relatively safe to assume that one is not over supplying P to one's soil just from compost.

I agree that phosphorus can be a major contributor to water pollution but doubt that much is coming from any compost source!! Unnecessary fertilization (typically from lawn and agricultural fertilizers) and fresh manures are the big culprits. As is the erosion or run-off of P heavy soils into streams and waterways. In fact, many states, including mine, have opted to seriously limit the amount of P contained in lawn ferts, even to the point of prohibiting its usage except for establishing a new lawn.
rgreen48
6 years ago
last modified: 6 years ago
Not to draw to far away from the topic, but to just highlight one of gardengal's points... yes, fertilizer runoff is a problem, but it's rarely from organic sources - like compost. The problem is from the abundance of 'synthetic' fertilizers that are water soluble, and in a chemical form immediately available to plants (including water plants, algae, and microorganisms.) I'm not suggesting that this would happen anytime soon, or that every use of synthetics is the problem, but if synthetics were not part of the equation, there would be no problem at all. Everything organic rots, and rain happens. Whether that rot is from manipulating the decomposition in a compost pile, the forest floor, or the soil surface of meadows around the world... compost is not really contributing to the issue.

And, as said above, an excess of any nutrient can cause issues in the garden - as well as with runoff of water-soluble nutrients.
perennialfan275
6 years ago
Gardengal forgive me if my posts sound stupid but I'm new to this and don't completely understand everything. You say that farmers who use ONLY compost actually have plants that are deficient in phosphorus. How is this possible? Many soils across the US have been tested and a lot of them actually have very high phosphorus levels, so how can there possibly be so many crops deficient in phosphorus?
gardengal48 (PNW Z8/9)
6 years ago
Levels of phosphorus are not going to be consistent across the board, just like levels of other plant nutrients will be extremely variable from location to location. P levels tend to be adequate - not overly high - on many soils, but those that have been routinely farmed (harvestable crops) or acidic sandy or granitic soils tend to have quite low levels of P and may very well need supplementation.

P levels in a residential garden only tend to be excessive if the soils receive routine applications of manures OR are heavily fertilized.
dustin2100
Original Author
6 years ago
Floral, I agree that I need to learn what I am doing before I invest more. I am actually learning that I probably need a lot less amendments in my compost. For instance, I didn't know that leaf compost has Ca, P, K, and a lot of trace elements. That would omit most rock dusts and kelp. I might need dolomite and something like feather meal and cut out everything else. I should have my soil test back by next Friday.

I also read that the amount of P that is shown on a Mehlich 3 test is the total number and not the available or mineralized amount of P. I read that amount of available P is a small amount of the total P, and I got the idea that the Mehlich 3 test is not a good test to check for P and it has been confusing me!

My dad is the one with open sunny spots. I would have to take a chainsaw to some trees. I don't like the idea of cutting living trees, but I am sure that a few wouldn't hurt. Here is the sunny spot in my yard and I have a hugelkultur bed that I would like to add to somehow. You can see how the shadows from the trees fall across my yard. These are pics of the north side of my property and this spot gets the most southern exposure. The hugel bed needs another top-dressing, I used perlite and it all seemed to come to the surface.
gardengal48 (PNW Z8/9)
6 years ago
dustin, I think the question is........why are you amending compost at all?? This is an entirely natural process that can happen just as effectively without any human intervention at all. All we do is speed things up a bit :-) But any organic matter will rot and decompose and that is all compost is......decomposed organic matter. Most gardeners just use kitchen scraps and yard waste - no amendments or additives at all - and create perfectly lovely compost with a full compliment of most necessary plant nutrients. There is no need for for kelp meal (although raw seaweed or kelp is a great compost ingredient) or rock powders or feather meal or even lime. They are expensive and unnecessary. If anything, these are considered amendments for ground soil, not compost, but even then may not be necessary additives.

All you need is a good combination of nitrogen rich 'green' ingredients (kitchen waste, grass clippings, weeds, seaweed) and a proportion of carbon rich 'browns' (dried leaves, small stems and twigs, sawdust or shredded paper and cardboard if those not available), mix in a little moisture and stir or turn now and again to add oxygen and you are good to go!!
rgreen48
6 years ago
dustin, one problem that you're going to have with those trees, aside from shade, is root encroachment. When you put a cultivated bed within the root zone of any tree, you can expect a large increase in the number of roots in that spot. Trees have the capacity to take up a whole lot more nutrients and water than any vegetable crop. and when you improve a soil for gardening purposes, the trees will fill the entire area with feeder roots in a season.
Whassisname
6 years ago
Dustin,

Your statements regarding M3 testing are not accurate and unfortunately your overall understanding of soil testing is not correct. Also, Soil Savvy is experimental and undocumented. Read their disclaimer of liability and their advisory on pH results.
floral_uk z.8/9 SW UK
6 years ago
last modified: 6 years ago
I'll second what G.G. says about compost. You don't need to be amending it at all. Amendments go into the ground, not the compost heap, and then only if they're needed.

I'm also wondering why you added perlite to a garden bed? It's used in container and potting mixes but what is the rationale for using it in a veg plot?

Your hugelbed appears to be right on the edge of the wooded area amongst the roots of the surrounding vegetation but you have a large space in the foreground of the second picture with much better potential for gardening. I'd try a bed there and keep it simple.
toxcrusadr
6 years ago
Gardeners often start out thinking they need raised beds with something special in them. One should not overlook the native soil. There are certain situations where raised beds are beneficial, such as heavy clay native soil that doesn't drain, or physical limitations of the gardener (can't bend over to work on the ground).

Your red sandy loam is a great soil and if your dad's garden has grown even marginally OK for years, add compost and plant in it! A soil test is OK but unless it's already very dark and rich looking you can't go wrong adding compost.

So maybe your solution to the earlier raised beds made of all compost is to till it into the top 6" of soil and plant in that. For new beds I would do the same thing. If they get so tall from the 'fluff' of adding compost, put some timber borders around them, but there's really no special need to construct raised beds IMO. In fact with sandy soil the drainage will be SO good that they will tend to dry out in the summer.

Soils become deficient in P on FARMS because of the harvesting of crops which have absorbed P from the soil. Also, clay soil can hold onto P very tightly so even if it's there, it's not very available. I wouldn't worry about adding compost made from typical plant materials. Come back in 10-20 years and if you have excessive P in your soil from adding compost over the years, we'll talk. :-] I bet you won't.
dustin2100
Original Author
6 years ago
Building a greenhouse is not that big of a deal and I don't know why everyone is scared of it. I am probably better at building than gardening. Here is my current project that I just finished... It should have been a greenhouse instead! I had help but I did everything from making a concrete form to the roof. Concrete is not that hard if you have a truck come and pour it...
dustin2100
Original Author
6 years ago
Here is the deal with the soil in my yard, the top 6-8'' is sandy loam but you will soon hit clay. There was a raccoon that got hit by a car and I had to try several different spots to bury it in... I was looking at installing fencing, but I would need an auger to dig holes through the clay. However, I can dig deeper holes in the wood-line.

My dad gave up on gardening because he didn't have a clue to what he was doing. He swore that it was bugs eating everything, "stuff would grow and die". Nobody in my family knows how to grow veggies and I am out here wingin' it...
dustin2100
Original Author
6 years ago
What I meant to say about the clay is that 8" into the soil it feels like I am hitting concrete.
floral_uk z.8/9 SW UK
6 years ago
Nice little hideaway. Nobody is scared of a greenhouse. Many posters who have tried to help you here will have one. The issue is whether it is worth you taking on that commitment of time and money to build something which will then require a whole new set of challenging skills when you are still coming to grips with basic gardening concepts. Being good at building a greenhouse is no guarantee of success in growing vegetables in one. Not to put too fine a point on it you are trying to run before you can walk. You've received a lot of down to earth practical advice but you don't seem keen to hear it.
dustin2100
Original Author
6 years ago
I got my test results back today from Soil Savvy. Again, my rabbit manure compost is off the charts in P and K! 15x too much phosphorus. I guess that I found my answer because this was basically pure rabbit manure that has been composted for 2yrs. Toxic levels of P and K... I am not even sure what to do with this stuff now

Here is the test results from my dad's garden. I am not going to be able to use the compost in his garden...
gardengal48 (PNW Z8/9)
6 years ago
Of course it is going to test high!! You are testing pure manure, not soil, and so a very concentrated nutrient source. However, once incorporated into the soil, as all manures should be, then the levels will decrease dramatically. You also need to be aware that these nutrients are not immediately available....only about 25% of the N in a manure is available during the first year after application and only 40% of the P. K is somewhat more readily available.

And you cannot make a direct correlation between what is showing on your soil test reports and suggested supplementation and the NPK of a manure like you would with a fertilizer. It just doesn't work that way :-)

FWIW, rabbit manure, even uncomposted rabbit manure, is an excellent organic fertilizer. It is NOT excessively high in any of the essential plant nutrients - no manure is - and can be directly applied to plants without concern for 'burn' or damage to young roots or plants. I used to raise rabbits as pets and relished the fact that they provided a very useful garden output that was never enough for my needs. I would actually pick and choose what plants to apply it to, with roses, clematis, lilies and any veggies getting the lion's share.
toxcrusadr
6 years ago
last modified: 6 years ago
^^ what gg said.

Worrying about the nutrient content of compost is like analyzing a cake for nutrition by looking only at the bag of sugar. "OMG there's too much sugar here!" Well, yes, but you eat the cake, not the bag of sugar.

I would amend the last paragraph about manure by saying that certain manures, when FRESH, have nutrients such as N in a form that can overload plants, which is why they're usually composted first. Hence the dead spots from dog bombs, followed by vigorous growth immediately around them. ;-) But rabbit in particular is apparently OK to put right on the garden.

Slightly related fun story: A composting friend of mine used to have rabbits, and she set up their cage directly over a big compost bin made of pallets. The rabbit pellets would fall right through the chicken wire into the compost. Presto!
dustin2100
Original Author
6 years ago
The test that I had done is testing for available nutrients. The nutrients on the test are the available nutrients, it's the "Soil Savvy" test.

My native soil already has an abundance of P, do you think that adding rabbit manure that has an extreme abundance of phosphorus is going to hurt anything??? This kind of thinking is what got me in trouble to begin with! Maybe, you guys live in an area with depleted P but it is in abundance here.
gardengal48 (PNW Z8/9)
6 years ago
P is not often depleted anywhere......unless under very arid desert type conditions or if the garden was previously heavily farmed.

And as stated several times previously, rabbit manure does not have an overabundance of P and even less if composted. You would have to add tons of the stuff to see any measurable difference.

Honestly, I think you are going about this in completely the wrong way and over-thinking things :-) Composted manures - in reasonable quantities - are an excellent source of organic matter and can be added to virtually any soil anywhere without concern........in reasonable quantities!!

And the title of your nutrient test says it all....."Soil Savvy" - not "Manure or Compost Savvy" :-)) These tests are not intended for these sorts of materials and are unlikely to provide an accurate assessment of them. And really, it is only agronomists that would be concerned about testing them in the first place.
Wayne Danielson
6 years ago
this has been an odd thread to watch develop.

dustin, you gotta settle down. You can garden for years and just barely scratch the surface of knowing what you are doing, and really, all you learn is how to manage the conditions you have. you can know a lot about how to grow...but know very little about how to grow in a new situation, a new set of conditions.

The original post is about high levels of certain nutrients. Original Poster later states that these nutrients exist in multiple forms, and not all forms are as available to the plant as others. Then later, laments the fact that he has toxic levels of these nutrients...but no indication of which of multiple forms are present. It's like there are two different people posting. Or that this whole thing is a rabbit hole.

Normally, for beginners, my advice is water, weed, keep a journal. Learn. The success of gardening in the first few years is only to a small degree measured by the produce. It's really about the learning, but you don't realize that until later.

My advice here is, get a crash course in learning to diagnose plant problems by sight. Ortho problem solver is a good place to start, the big one. Then...despite the lament of too much of whatever...have you tried fertilizer* when your plants have shown signs of distress? Not a lot, just a little, just to see what the response would be? Sounds strange when your soil test says you have a lot...but you can die of thirst in the ocean. Just because you have it does not mean you have proper amounts of the right form...and as long as you don't get a proper soil test, you will never know.

*I'm not offering legal advice. Disclaimer not needed, but will be provided anyway. Can't wait to hear the distress that will be created because I recommended a book with ortho in the title.

Your complaint about your compost measuring high is kinda like complaining that your mattress is too soft because you have soft sheets. You are stuck on half the story, and you're constantly hitting repeat.
gardengal48 (PNW Z8/9)
6 years ago
Wayne, actually the Ortho Problem Solver is a great reference book!! May be expensive overkill for a home hobby gardener but it is used as a resource by the Master Gardener program and we use it as a standard reference at my nursery. We don't always follow the text's recommendation to treat with an Ortho product but we can at least evaluate the problem with a reasonable degree of accuracy. We also have another, equally massive publication compiled by our extension service....but without the photos to illustrate and without the focus on an Ortho product to control.
dustin2100
Original Author
6 years ago
Your right, I am far from an expert! Also, I have been diagnosed for TBI from being hit with IED's. I am not as sharp as I used to be... It will explain my irritability too.

My train of though. When I put down a generous amount of my compost, I usually have nothing but problems the first year. I had my soil and compost tested and they were both high in P. I didn't want to spread a problem that would be hard to fix later.

I expected my compost pile would make the lawn green around the area, but the lawn next to the compost is bare?
floral_uk z.8/9 SW UK
6 years ago
The area round your compost heaps is a heavily trodden spot under trees. You can't expect grass to grow there well.

When you say you had your soil tested was that the native soil in the ground? Your best plan is to dig over a bed in the native soil away from the trees and add a few inches of your compost as an amendement. Don't grow in just compost. Don't grow in just manure. Grow in the earth nature has provided and use your compost and manure as an amendment to improve it. And there's no need to make a lot of separate composts. The leaves, grass mowings, rabbit manure and all other kitchen and garden waste can all go together into those impressive pallet bins. I think a lot of your perceived problems are due to overcomplication.