Soil Test Results! Are Compost, Worm Castings & Mulch Enough?

One of my goals when I started this channel was to show how we give our plants all the nutrients they need using only compost, worm castings, and mulch from free, local, and abundant resources. In the past, I’ve relied on garden results to prove my point, but today I’ll put this claim to the test with a soil test Here in the US, soil testing services are provided at a reasonable price by college or university affiliated agricultural extensions. In Illinois, the University of Illinois Extension provides a list of labs that provide testing services. I decided to go with A&L Great Lakes Laboratories because of their clear instructions and easy to read reports. I chose their $30 complete test, rather than the $20 basic, because it tests for a wider variety of essential plant nutrients. I decided to test the soil in the spring – a time when many nutrients are likely to be at their lowest levels. I haven’t applied compost and worm castings in nearly a year, and last year’s crops certainly took up nutrients that have not been returned to the soil. Following instructions from A&L, I took four separate samples of garden soil, digging down to a depth of about 8 inches. I combined the samples in a bucket, mixed them together thoroughly, placed one cup in a plastic bag, and sent it off to A&L. To my pleasant surprise, the results were ready in only 1 week. Though I had hoped for a dramatic letter opening to reveal the results, consistent with the times, they came in an email. First, I’ll share the results line by line. Then I’ll discuss how I plan to respond to them going forward. Let’s start with organic matter, which improves soil tilth, adds nutrients, and helps soil hold nutrients and water. Not surprisingly, after years of applying compost, worm castings, and mulch, the amount of organic matter in the soil is very high at 20.5%. Next, let’s look at the essential plant nutrients in the report. We’ll start with phosphorus and potassium, which are often added by gardeners via NPK fertilizers and other amendments. Phosphorus plays a number of key roles in plant health, including photosynthesis, the development of healthy roots, and flower, fruit, and seed production. The phosphorus level or our soil is very high. Potassium, which plays a key role in almost all plant processes that support plant growth and reproduction, is also very high. So, clearly, compost, worm castings, and mulch from free local resources added more than enough phosphorous and potassium. and additional fertilization was completely unnecessary. Now let’s look at the rest of the essential plant nutrients in the report. Magnesium is high. Calcium is medium. Sulfur is medium. Zinc is very high. Iron is high. Manganese is medium. Copper is high, and Boron is very high. So, at a time of year when nutrients are likely to be at their lowest levels, there are no deficiencies of any of the essential nutrients listed in the report. Of the 10 tested, 3 are at a medium level, 3 are high, and 4 are very high. Now let’s look at sodium, the only non-essential element in the report. The sodium level in our soil is very low. Fortunately, this is a good thing, because high levels are very detrimental to soil and crops. Similarly, soluble salts are very low. High soluble salt levels are often associated with the use of synthetic fertilizers and are detrimental to soil and crops, so it’s good to have a very low level. I was very pleased with the results for cation exchange capacity, which reflects the ability of the soil to hold nutrients. The cation exchange capacity of our soil is high, which means there’s a high capacity for negatively charged clay and organic particles in the soil to attract and hold positive soil cations such as calcium, magnesium, potassium, and ammonium. I have to admit. I was a little surprised by the next result, but I really shouldn’t have been. Soil in the Chicago area is often alkaline because the area sits on top of a bed of limestone. So, I shouldn’t have been too surprised that our garden soil is also slightly alkaline, with a pH of 7.3. This result confirms a point I’ve made a number of times – namely that used coffee grounds will not acidify the soil. We’ve added thousands of pounds of used grounds to our compost over the years and the soil pH remains alkaline. Large quantities of wood chips and autumn leaves have also not acidified the soil. Before going further, I should probably also talk about nitrogen. Though most inexpensive soil tests, like this one, don’t test for nitrogen, A&L did recommend fertilizing with nitrogen. Nitrogen moves through the soil more quickly than phosphorus and potassium, so it’s more likely to become deficient when we reduce our compost applications. To compensate for this, we’ll grow more nitrogen fixing cover crops and we’ll let our plants tell us if they need more nitrogen. Though it’s possible we may have to resort to a nitrogen fertilizer at some point, I’d bet money that the cover crops will be sufficient and no fertilization willbe required. I’m very pleased with much of what I saw in the soil test results. First of all, it’s clear that compost, worm castings, and mulch from free, local resources have provided more than enough nutrients for our plants to thrive. In fact, A&L Great Lakes Laboratories doesn’t recommend adding any fertilizer to increase any of the nutrients that were analyzed in the test. However,I am concerned that some of the nutrient levels are too high. High phosphorus, in particular, can contribute to water pollution, inhibit mycorrhizae, and create nutrient imbalances that interfere with absorption of other nutrients. I’d also like to bring the soil pH down to within the optimal range for vegetables, which is between 6.5 and 7. I hope to gradually reduce the nutrient surpluses by making significantly less compost. We’ll continue to feed kitchen scraps to our composting worms and compost the rest of our household organic waste, but we’ll no longer compost additional free resources like used coffee grounds and autumn leaves from the community. This will reduce the amount of compost we produce significantly and hopefully bring down nutrient surpluses. Though I still strongly recommend composting free local external resources to bring nutrient levels up to optimal levels, our soil has reached the point where, at least for now, this is no longer necessary. Next spring, we’ll test the soil again to see if we’ve brought the surpluses down. We’ll also check to see if nutrients that are currently not in high surplus remain at sufficient levels. If they dip to lower levels, we’ll address them individually. I also hope to gradually bring soil pH down to optimal levels by applying sulfur. Vegetables absorb nutrients more readily, and are generally more healthy, when soil pH is between 6.5 and 7. Again, a soil test next spring will tell us how effective the sulfur applications were and let us know if adjustments are needed in the future. Well that’s all for now. Thank you very much for watching, and until next time remember you can change the world one yard at a time.

92 thoughts on “Soil Test Results! Are Compost, Worm Castings & Mulch Enough?

  1. Patrick, I'm so glad to see your soil test results. This is really inspirational. I'm so glad to follow in your footsteps as much as I possibly can.

  2. Hey, Patrick! Great report, and well presented, as usual. I'm enjoying your beginner series a whole lot!

    QUESTION: Since most of your beds are filled with your homemade compost, how are you gonna address future shrinkage issues? Is that when you'll start making compost again?


  3. It will be interesting to see how effective you are in reducing your soil pH. It should be easier on a smaller scale, like around a blueberry bush. How did you estimate the quantity of sulfur to order? Do you expect to change the pH of all your raised beds?

  4. Do you have any idea or would like to take a guess at when the phosphorus levels will start to drop Patrick? 
    Cheers sir..

  5. I wouldn't worry about pH, it is a waste of your time and money.  Dr. Ingham blows away the myth of pH. Since when, she asks, has nature said a pH 6.5 is ideal for crops, when they grow successfully in ranges from 5.5–11? Soil pH varies so widely even along a root hair that an average value is meaningless. It isn’t the soil pH that needs analyzing, it’s the soil’s microbial life, and I am sure yours is terrific.

  6. Really nice results my friend! Mother nature knows what she's doing. Be careful about sulfur, it's a very good an antifungal…with no discernement!!!

  7. Interesting video on the test from your soil. Is organic matter something you really want to decrease even though it was high on the reading? I would think you could never have enough organic matter since it's always being broken down to it's smaller molecular ingredients.

  8. In your worm bin, do you have any BSF larva eating?  I began a worm bin and before I had a chance to buy wigglers, the BSF had laid eggs and there were larva devouring everything.  I'm not sure if their castings are beneficial or if the two can coexist, though I've read the wigglers eat the castings of the BSF larva.  Thanks.

  9. Well congratulations Patrick. It looks like your hard work has paid off. I have to admit I was not surprised by your great numbers as you obviously work hard to maintain a great soil system. Good luck this year with the garden.

  10. Isn't this amazing! You are actually going to implement no nothing gardening this year! Next year's soil results and progress of your plants this year will be an interesting watch. Super informative video, thanks!

  11. Very good results! I've seen two cases where organic gardeners had their soil tested and were shocked to have extremely deficient soil after thinking it was very rich all along. You're definitely doing things right!

  12. I have the same high alkalinity problem (in fact, a touch worse), Patrick.  I'm wondering if there is something natural but slightly acidic we can add to decrease the numbers to the right range (besides sulphur – I might try to check out the wood/pot ash).

  13. @OneYardRevolution | Frugal & Sustainable Organic Gardening your garden is a beautiful example to all of us. Thank you for sharing with us. This is very encouraging to us more inexperienced gardeners 😉

  14. Thank you, Patrick for a great video. Your garden looks good right now.  So much green.  Take care my friend and have a wonderful gardening season.

  15. So Did I miss it or As of this Test you do not know nitrogen levels in your soil? If you do not know what are you planning to do to find out?  Thank You Patrick

  16. Stellar results!     It is so good to know that you can back off all that hard work to make compost and now refocus on just the weak areas.       I normally test the soil I have amended and also do a test of soil I have not, gives me a baseline of what my changes are doing.       The next level up in testing is a plant tissue test.    That helps to know if your plants are getting the nutrients that you have put there.

  17. I'm glad you did a soil test, it shows what your doing Works, I'm going to do the same, well I've already started, I've got my greenhouse planted with toms and Q's all in compost from the compost bin, my worm bin is working albeit a bit slow at the moment and I'm making compost tea.

  18. Wonderful! Great to know that the amendments are working and that it might also be possible to add less to the soil.

  19. I just got my results last week and had  a lot of the same results you had. Same recommendation to only had Nitrogen to the soil.  I am a little concerned with the high levels of P and K in my soil so this year I am going to  add no additional amendments as well. My ph was a little high too 7.7 and hope to improve that to make life happier for my plants. Your video was well stated and help me understand my results and relax thinking that I had horrible results.

  20. Afternoon everyone I have some more news I have a few more asparagus spears up today!! Red onions are doing good and scallions…Got to plant the rest tomorrow daikon  and carrots beets and collard greens kale busy busy!!

  21. that's interesting that you have such an alkaline result in your garden soil when it is mostly compost you added and not mixed in too much with the native soil just sitting on top of it. Makes me believe even more that after maybe one or two more years of adding soil conditioners like compost used coffee grounds and grass mulch and leaves on my soil that i will have enough nutrients in the beds to grow anything i want with out much worry or work.

  22. I thort you didn't like useing chemicals in your garden why use sulfer ? you could just brow up some coffe and water you beds this will also bring down the PH also rasesing your N levels I like to give my patatos a good watering with coffe at least twice in the growing seson

  23. Thanks for sharing your results and I am glad you got them so fast !  I knew your numbers would be off the chart but did not expect four of them to be maxed out !  I am so looking forward to your videos on cover crops.  I experimented with two varieties this year; Annual Rye and Mustard.  I had the impression that the rye would eventually die back like the mustard did but boy was I wrong.  I am trying to be no till but I have had to chop, drop, and then turn under the rye in order for it to start breaking down.  I have heard that nitrogen fixing legumes will be about the same.  I am still not done turning as it has been more back breaking than I thought.  Maybe in 3 – 5 years my beds will approach yours in fertility.  Take care !

  24. try some heavy feeders and see how they yield in one or two beds. then when you retest, you can isolate a sample from that area and see how the soil reacted. Its all a balancing act. great video and results!

  25. Congrats on your results! It just confirms that your approach is working. Looking forward to following your efforts this year.

  26. Over 20% of organic matter? Wow. Is it not the case that conventional cropgrounds struggle to have 4%? By the way- the soil in your garden looks amazing- so dark and crumbly. It illustrates the point- if an ecosystem, no matter how small is not depraved of nutrients and not disturbed it will bring all the life-essential factors to an optimum level and maintain it.

  27. Thanks for all the videos Patrick! You might not need all of those scientific 3rd party tests to confirm your results. Dr. Ingham shows you why. Also, 20% OM, that is nuts. Just keep doing what you're doing, maybe nix the tea sprays. Check  out this recent talk and take from it what you can;

  28. Another excellent video Patrick. Thanks. I'm a little confused about the nitrogen issue though. Is their recommendation just a general one since they didn't actually test your soil for nitrogen?

  29. Composting neutralizes the PH of coffee grounds.  Apply coffee grounds directly to the soil surface and then take a PH test after a week; you will see the acidity increase.

  30. Patrick, I have been thinking about this video almost everyday since I watched it almost two weeks ago.  It is very thought provoking, especially the part about the low nitrogen levels.  Do you think this might have something do with the nitrogen in your soil being unavailable but present in the microbes?  I've just read Teaming With Microbes and that book makes it sound like the nitrogen gets locked up in the various organisms and is available over time as they die and are consumed.  Is it possible that you have sufficient nitrogen, but it isn't measured when it is all locked up in the biology? Perhaps you might see a different value if your measured your soil later in the year when the soil is super active? Anyways, great video!

  31. Hi!
    Got my first lettuce garden planeted in early April and now the baby lettuces have a problem.  The leaves are turning white and yellow!  It is quite alarming.  I have watered them on a regular basis and then stopped this week as I wondered if I was giving them too much and this problem was a mold.

    But, the yellowing and whiteing of the leaves has not stopped and is worse each day.  What's wrong?

    Barb R.

  32. Hello, where do you get the free compost, worm castings and mulch from? Please provide resources to get them for free, living in Santa Clara, CA.

  33. OMG! These result are impressive! I can't believe your soil has 20% organic matter! Good Job! Question for you on pH and growing berries. Do you grow any berries( which generally prefer a lower pH )? If so, do you add sulfur to lower the pH?

  34. Want a free and natural nitrogen fertilizer? Pee 🙂 Dilute it 10:1 and you're good to go.  Thanks for sharing your results

  35. I have seen old growth forests results showing that the soil is super low in nutrients. There is no way that those giant biomass accumulations happen with no nutrients. So I don't pay much attention to those tests.

  36. alkailnity is most likely from aluminum from geoengineering. Please give some time to9  Thanks great vids, i'm a new subscriber today. Peace -Ben

  37. Thank you, for the grate information you have received by testing your soil. Do this mean that wormcasting is all you need if enough is surplussed?

  38. Patrick, I really like your informative and concise videos. I am in Chicago also and got a soil test from the same lab you used last year. Very similar results to yours, including a PH of 7.5.
    What brand of elemental Sulfur did you choose and where did you get it?
    Most of what I have found is in smaller 2 – 5 lb bags.
    Thanks Michael

  39. Love your focus on the low cost side of gardening. There is no need to invest in fancy fertilizers/soil amendments, your basic gardening soil mix of worm casting/compost/mulch is more than adequate to produce fine vegetables.

  40. I have a perhaps silly question. If you add so much compost every year, every year that you apply do you have to remove some of the soil in your beds to make room?

  41. I really doubt you will have any nutrient runoff due to high levels of microbial activity. Phosphorus pollution should only be a problem with chemical fertilizers. I really enjoy your channel….thanks for the videos.

  42. Patrick has this soil testing laboratory changed it's website/reports since this video?  I'm looking at the website and options for reports and it does not look similar to the report you received.

  43. I would not stop composting. it is great you have plenty of nutrients that can be converted available my bacteria to growing plants. also I would have another lab such as a university run soil test. have you thought about testing your castings or compost separately?


  45. Compost= phosphorus it's the highest source of phosphorus organic farmers have other than poop bonemeal and rock phosphate

  46. Thanks Patrick. I'm in the process of improving my soil. It is pretty poor a the moment and we seem to get a lot of pests and diseases. Did you find that this decreased as your soil improved over time?

  47. You've done a great job with your soil Patrick. Thanks for showing there is a better way than just throwing store bought MPK into your soil. Since watching your channel and others like it. I've started composting about everything using worms, bins and chickens. The chickens really compost fast btw. I can't keep enough fall leaves in their pin. Anyway thanks again, your knowledge is a great resource. Hey how about a video of some of your songs? You play really well.

  48. For a N source use 21-00-00 as it would also reduce to PH a little. The higher PH is not a problem except maybe raspberries. Just put a few oz of 21 ( AMS) near the acid loving plants. For compost use pine bark or course wood chips for slow decomposition. For every time you are adding OM to soil you are sequestering N that the plant cannot have access to until mineralized.. The 1/2 life of OM in a northern soil is about 30 yrs. Lowering the OM 5% points gives 350 lbs of N for a 1000 square foot garden. 15 yrs to do this if no compost residue is added.

  49. I also made a soil test in 2015 and I have similar results, but I have a high value at salt. What can I do to reduce that? I don't use any chemical fertilizer in the last years. I also use wood chips and I add horse manure two years ago. I should only add some nitrogen

  50. Hi Patrick, I’m a new subscriber and gardner, I want to thank you for your very informative videos and let you know I’m working changing my little plot of land also.
    Where does one find free worm castings?

  51. What do you think about Steven Solomon recommendations? He also recommends soil tests, however he chooses different desired values than standard ones. Basically he is looking for high nutrient values in the plants that grow in that soil. I wonder, if you ever tested your vegetable mineral/protein content? Teeth/bone/nail/hair health would be first ones to show, how nutritious the food is, if majority of our diet comes from our garden.

  52. Brilliant to see some testing done on the various claims made on various organic adjuncts. It would be interesting to see if products like zeolite and diatomaceous earth, humic/fluvic (additives) and kelp/seaweed work, or whether they too are a waste of money.

  53. A little bit of a waste of money, but it might have been interesting to send the same soil sample to two different labs. You really have the ideal set up going and the proof is in your production and also this test result that we do not need to add fertilizers to our soil. Probably the last easy piece is to simply have a home aquarium and occasionally use the fish water to water nitrogen-loving plants at important growth stages.

  54. NOTE: USED COFFEE GROUNDS DON'T DECREASE ACIDITY IN SOIL! While, coffee grounds ARE acidic, the pH becomes neutral when you make the coffee as the acidity is drawn out into the coffee you drink. So, to decrease pH, you can use Azeleas mix, Sulfur I believe, and cold coffee which has the acidity of the grounds. The grounds, once are used and no longer acidic, is just a good fertilizer that has fair amounts of NPK and other nutrients.

  55. Sometimes chasing numbers is more trouble than its worth.

    Also I love your channel. I just bought a little house down here in Clearwater FL, zone 9b. I want to follow in your foot steps my friend. two yard revolution haha. Thank you for all your information and passion.

  56. That is amazing that you are bring down the nutrient density of your soils. Here in Utah, the native soils are very low in nutrients and organic matter and high in sodium and salts. I’m pretty close to “the great salt lake” if that tells you anything. I’m building my soils by adding as much OM as I can get, but it is rarely free. Your videos are a great help and inspiration.

  57. Hi Patrick, Is vermicompost alone sufficient for root crops like potatoes,carrots etc ? Or do you suggest adding bone meal ? The reason i ask is it is difficult to find good qty of rabbit manure here. Is rabbit manure a good option for phosphorous ? are you considering adding rabbits for manure as part of your eco system ? Thanks

  58. maybe if you sift the nitrogen stealing wood out of your compost youl have more nitrogen? that's if theres even nitrogen in finished compost lol I'm not sure how it works, I guess the nitrogen comes from the things that eat and poop it out

  59. Is it possible that when you lower the pH of your soil, the nutrients in the "very high" category will be more available to plants, thereby decreasing those levels when they are taken by the plants? Maybe after a couple years of a pH between 6.5 and 7 those levels will be considered "high" instead. Thinking out loud…

  60. i planted a few plants in different mediums and the 2 compost only plants were deficient in nutrients so i gave 1 a bit of wee and it greened right up and actually now looks better than the ones in pure loam which both look good with or without urine, can you explain what the hell is going on cause i just cant figure this stuff out, if i let my compost get processed by worms first would that make it a better for a planting media or would it still need urine? is it just that the nitrogen is getting used up to break stuff down and that only the compost tea that trickles into the soil carrys free nitrogen or something? man.. this gardening stuff is insane my head just cant even lol ive even head that 20 percent organic matter woud just rot out trees roots… does organic matter make the soil even more rotty cause gary matsuoka says you cant really improve clay for root rot you can only plant on top of it in top soil or sand or replace the clay completly, and i remember a gardeners world episode where monty was saying no matter how much organic matter he tilled into the soil he still had bad root rot problems and he adds grit to try fix it but has never had luck, i have all this compost and all these hopes tho yano lol the thought of creating your own soil seems like the only sustainable way for container gardening otherwise id have to order in top soi or make ppot holes in my garden and no thankyou lol

  61. Aphids attack plants that have been fed liquid nitrogen and/or too much of it. Feed coffee grounds to your worms. They will produce chelated Nitrogen (that is bound to an amino acid) which your plants can uptake. Ditto for minerals. Feed egg shells to worms (after the shells have been, washed and then sterilized or baked in a 375 degree oven for 10 minutes.) The worms will produce chelated calcium which prolongs the shelf life of vegetables and an enzyme called chitinase which digests the exoskeletons of aphids. One whiff of chitinase and those aphids fly away.

  62. About a decade ago I had a soil test before I ever dug. It was so good, they left a hand written note explaining its goodness and advising addition of nitrigen in the event I was going to grow wheat or corn (typical ag, here). I've done a lot of different gardening methods, but this year I'm going no dig and I'm never going to touch it. I've wonder about excessive nutrients. My clay needs more fluffy through applications of leaves and the plants need compost to stabilize their nutrient uptakes, but I think I'll keep it to about 1" a year. Our soil life eats a lot of the organic materials and are effective composters. So many critters in the ground!

  63. I have a few questions:
    Does compost nutritions is affected by what type of waste you pile to make it? Like applying calcium rich waste will increase calcium in the compost does it work this way?

    How often do you fertilise with compost?

    And another question that is off topic how do you prevent wood planters from rotting what type of sealing do you apply?

  64. Something interesting I've learned is that used coffee grounds aren't acidic. Apparently, we drink the acidic part and what's left is pretty neutral. Your test results verified that.

  65. lol 20 % organic matter ! That's crazy. A normal soil, like a wild meadow or forest, is 5% on average. You don't have to go higher. Tilled fields in France are now in jeopardy because their OM is at 1 or 2%… It takes those farmers 2 years, and 400 tons of wood chips or straw per hectare to bring those soil up by only 1%. So if your soil was at 5% initially, like most natural soils, you added the equivalent of 6000 tons of wood chips per hectare lol.

  66. Calcium is the #1 deficiency for gardeners indoors or out… if you're trying to add Calcium and Sulfur at the same time without increasing pH levels I would use Gypsum (rock dust), you can buy a 40-50 lb. bag of powdered Gypsum for ~$5-8 USD at Home Depot/Lowe's

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