DLup
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Input on soil test results

Hi all,

I posted this in another forum, but I lurk here too so I figured I would ask around here...I am looking for input on my new soil test results. I have been looking around here and elsewhere online, but I figured I would see if anyone had any thoughts for actions I should or could or shouldn't take.

First some background so you know what I have been up to and then the soil test for which I seek feedback.

I have been using square foot gardening in four small raised beds for vegetables (including every year tomatoes, peppers, kale, collards, beets, eggplant, zucchini, garlic and some years various others like cabbage or tomatillo). Three beds are 3'x4' and one is 2'x4'.

I started with Mel's Mix and have added my own compost each year and last year added my own compost, a year old bag of manure, a couple other bags of compost or other organic rich amendments, some many years old and well-composted sheep manure, greensand, and azomite, all in an effort to counteract compaction and decreased productivity and loosen the soil mix, which I am not sure really worked on any counts; the new ingredients were thoroughly mixed in last fall.

In the past I have used blood meal and added bone meal when planting and for the last two years have used a Fox Farms balanced organic fertilizer both when planting seedlings and once or twice as side dressing, and also a couple applications of fish emulsion as a combo drench-foliar feeding.

Productivity of fruiting varieties has decreased over the last couple years noticeably, but collards and kale certainly seem to do fine and in general plants seem healthy, just not so fruitful.

We had terribly success with direct sowing this year with low germination and damping off of most plants that did germinate. Given the decrease in productivity and poor germination/damping off (and the soil texture from the test...see below), I suspect I have drainage problems at least if not also fertility.

Now to the results and my comments in parentheses. These are from the UM soil lab, which provides relatively meager tests for the home gardener. I chose not to pay for determinations of SO4, Zn, Mg, Cu, Bo, or Pb. I would be most obliged to get any and all thoughts and reactions to the information above and that below.

Thanks!
David

SOIL TEST RESULTS
Organic matter: 20.8% (because it is basically Mel's Mix)

Soil texture: muck (Presumably because it is Mel's Mix. I plan to add some medium sand and very coarse sand-fine gravel this fall to work on the texture and improve drainage)

Soluble salts: 0.4 mmhos/cm (no concerns at all)

pH: 7.2 (I think just past the high end of ideal, so maybe I do nothing? Add sulfur?)

Phosphorus: >100 ppm based on Bray 1 extraction (this is the one that for sure puzzles and confused me...Not sure why it is so high unless it is a result of past additions of relatively small amounts of bone meal, the additions of aged manure last year (one bag of steer, two kitty litter tubs of sheep), or just from adding compost regularly. Do I do anything other than avoid manures and any amendments/fertilizers with P?)

Potassium: 180 ppm (A little high, so maybe no greensand for a year?)

Calcium: 2628 ppm

Magnesium: 314 ppm (I think the Ca and Mg are ok and the ratio is about right)

Fertilizer recommendation: 0.1 lbs/100 sq ft of N and K, but no P (seems pretty generic)

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rainbowgardener
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Can't comment really about the test results, but given that you clearly have rich organic soil, I'm thinking that the compaction and lack of drainage ("muck" doesn't sound good!) is the biggest issue causing poor results. Another clue to that is that you had damping off. I always have to be careful about that with starting seeds indoors, but have never had any damping off issues with outdoor planted seeds. It's a sign that your soil is holding moisture too much (all that peat in the Mel's mix).
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DLup
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possible solutions for drainage?

Hi rainbowgardener,

To help loosen the soil, decrease compaction, and increase drainage, I had planned to mix in my compost (primarily last year's leaves, grass clippings, other yard waste, and kitchen scraps), fine sand, medium sand, and very coarse sand/fine gravel (crushed rock at about 1/8" grain size). I will also mix in the straw and grass clippings I have on top now for mulch.

Anything else you would suggest? I was thinking maybe pine bark fines if I can find them.

David

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farmerlon
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I would only mix in the straw and pine fines if the beds will be sitting dormant for a while. Otherwise, you're likely to have a nitrogen deficiency for your crops while those materials are decomposing.

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applestar
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I think fine sand might be counter-productive.

Also, I believe you need to be careful about what kind of rock/gravel since you are trying to lower pH. Granite/marble dust helps me raise pH. Quartz sand is probably inert.

When adding home made compost to my garden with clay subsoil, I only "screen" through approx. 1.5"x2.5" wire fence -- just enough to take out larger sticks, whole corn cobs, lumps of clay sod etc. -- to help vary aggregate sizes.

Cincinnati
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Re: Input on soil test results

First, I see a few raised flags. So we need a bit more information.

What else is in your mix? Did you start with 1/3 compost, 1/3 peat moss and 1/3 Vermiculite? Your mix should test at 67% organics. Compost is organic. Peat is organic. Vermiculite is the only non-organic material in your mix.

Your mix texture is "muck" says you do not have MM as your "soil".

MM by design does not compact, at least not in the way a soil compacts from walking on it. If you're trying to make the mix more friable, adding vermiculite is a solution.

Manures are high in Phosphorous. That would account for your high test result.

Do you have bottoms on your raised beds? If so, how many drainage holes and what size are they?

If the bottoms of your beds are open, when you add compost and other ingredients, are you digging into the soil below the bed and pulling it into your mix? This would account for the much lower organics component in the test result. It may also account for other symptoms and results - like the texture.

Are you having the same issue in all your beds?

All these descriptions indicate to me that you may need to start over with your mix. I've used MM for three seasons. I definitely have none of the mechanical problems you describe with the soil. In fact, the properties of my mix is almost the opposite of what you have.

Questions aside, I like what you're attempting to do with your SQFT gardens. Compost alone can't create the perfect soil balance of nutrients and elements. I believe a soil test is needed to know what we are dealing with in any soil.

imafan26
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It might be a good idea to let it dry out. You should only need to water when needed. If it is the rain that is keeping it wet, can it be covered?

I had similar soil test results. Poorly draining soils will keep the pH relatively alkaline. Nutrients K,Phos, may be high in the soil test but not avail to the plants so they will not grow well. Micros uptake will also be restricted. Nitrogen losses accelerate. Phythoptera, dampening off, yellow stunted growth are all possible. Shallow rooted and plants that like alkaline conditions will do better than acid loving. Plants can be healthy but will usually be relatively short.
Happy gardening in Hawaii. Gardens are where people grow.

DLup
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Hi all,

I just noticed the recent response from imafan26 and realized that I had somehow missed Cincinnati's post from September despite checking in here every week!

Cincinnati I hope you are still around and stop in and see my responses. I am having the same problems with all four of my raised beds. As I understand, a muck soil is one that is very high in organics. Given that I added even more organic materials in addition to the base MM and the repeated additions of compost, I think the term makes sense for what I had in my beds. I did start with the 1:1:1 mix of ingredients for MM and continied to add compost. My beds are 12" high and not closed bottomed but sitting on the original soil of the bed, but I never get all the way down and mix up original soil when I amend. I have tried adding just vermiculite too at least once, but it did not seem to help and my sense is that the vermiculite breaks down in grain size pretty quickly. This fall I added an inch of pine bark fines and an inch or more of a range of sand (fine, med, a mix that includes coarse, and some very coarse sand-fine gravel). That seemed to help the texture, but we'll see what happens after the winter and over next season! This actually takes me pretty close to the original MM, which was 3 parts compost, 3 parts vermiculite or perlite, 3 parts peat, and 1 part sand.

imafan26, it seems like the drainage problem is only early in the season, and perhaps I was over watering. Later in the season here these days (well, summer days), we don't get rain that often anymore. We can go weeks with no rain, so I have a microsprayer irrigation system for my veg raised beds and all of the perennial beds. Tinkering with that is almost as much fun as the gardening itself! After about early June, the raised beds dry out pretty well between waterings and the mix gets very hard when dry. I am hoping that with the additions of sand the mix will drain (i.e., dry out) better earlier in the season and won't dry as hard later in the season between waterings.

Finally, I am going satisfy my gardening jones during the winter this year and start many of my veggies inside under lights. If I can get that to work, then I will have solved my germination problems in the beds even if I have not solved my mix problems!

imafan26
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I think adding coarser materials like sand will help to aerate and should help a lot with drainage and the beds should dry faster. Starting seeds in pots is probably a good work around. I have to wait until my soil is friable before I attempt to plant anything after it rains a lot. It also helps to plant by the moon. I don't know why it works, but it does.

https://www.gardeningbythemoon.com/phases.html

https://www.the-gardeners-calendar.co.uk ... anting.asp
Happy gardening in Hawaii. Gardens are where people grow.

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ElizabethB
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Hi and welcome to the forum. This was a university lab test? There should be contact number for your county agent. The CA gets a copy of the results and is there to translate and make recommendations. I KNOW - in some regions the extension offices are really not available to home gardeners but since you were at least able to get the test done you may also be able to get it translated. pH does seem to be a little high but before amending see if you can get in touch with the CA. Did you have your samle processed through the extension office or directly through the university lab? Either way you should be able to contact one or the other for a review of the test results. They will tell you exactly what and how much you need to amend your soil. There is no additional cost for the consultation.

From what I have heard from other forum members you are lucky to have been able to have your soil tested. That is an indication that you may actually have a responsive extension office.

Good luck
Elizabeth - or Your Majesty

Living and growing in Lafayette, La.

When weeding, the best way to make sure you are removing a weed and not a valuable plant is to pull on it. If it comes out of the ground easily, it is a valuable plant. ~Author Unknown

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