4.3: Amendments - Physical Fixes

A soil amendment is not a fertilizer – at least not in my book - Valerie Dantoin.

Amendments basically amend, change, and correct things–for the better. They usually have an effect on a soil's physical structure or biology.

One can argue that fertilizers change things for the better–but not in the sense of actually changing the soil quality itself. A fertilizer's primary “job” is to add nutrients to the system that will be taken up by the plant, while an amendment’s job is to alter the physical, biological, chemical, or structural nature of the soil. This in turn will increase nutrient availability for the crop or plant. A later chapter is devoted to fertilizers.

This is why I think of compost as an amendment rather than a fertilizer. Compost primarily changes soil by adding organic matter, microbial life, and humic acids rather than NPK nutrients. A compost-amended soil is a higher quality soil than it was before the amendment. Therefore, when a person does add fertilizers to soil with compost, the response may be more amplified than if fertilizing unchanged soil.

There are many books and articles that examine organic soil amendments. There are workshops and conferences devoted to the topic, but in my opinion, they get amendments confused with fertilizers. They also confuse “organic” with “carbon-based”. Most amendments are organic in the sense of using carbon building materials, but they are not certified organic.

In my experience, there are very few worthwhile soil amendments, especially commercially available, decently priced, and that give repeatable results. Just about any commercial organic grower should make their own amendments rather than buying them. This is actually a key to profitability in organic enterprises.

Humic acids are worthwhile soil amendments, but they are expensive to buy. Make your own by further refining your composting techniques. Adding soil conditioners as amendments - like peat moss or sawdust is OK, but they need to be from organic approved sources. Also, they are not practical on a large scale. Figure \(\PageIndex{1}\) summarizes some great organic soil amendments as well as some manures. We will discuss manure further in Chapter 10. The publication from which Figure \(\PageIndex{1}\) came is from a 1998 University of Wisconsin extension bulletin. Notice that it calls these materials 'wastes'. It is never a waste to put organic matter into soils! That publication also lists other soil conditioners like leaves, food wastes, grass clippings, fruit wastes, peat, cornstalks, straw, sewage sludge, and even wood as materials to add to your soil--albeit more easily done in a garden situation than on farm fields. Most of the time we add these as composted materials rather than putting them directly into our soils. We will discuss composting further in Chapter 9.

Remember that other bulky amendments may act both as soil conditioners and fertilizers. Examples include green manure crop and cover crop plow-downs, and crop residues.

Figure \(\PageIndex{1}\): Compositions of Miscellaneous Wastes. E.E. Schulte & K.A. Kelling, UW Extension. Organic Soil Conditioners

In general, you will find true organic soil amendments good, but too expensive to buy for commercial field-scale use. Avoid “sexy” products in eye-catching spray bottles. The best way to fix your soil is to harness your own microbial workforce. The compost you make yourself is your best bet. It is not as fun as buying products, but it will make you a true organic matter, soil-building farmer. Build your soil tilth through methods like fallowing, green manures, cover cropping, and composting.

You will want to check with any company you are thinking of buying a product from to make sure that their product is certified organic. Some companies mistakenly (or not) use the term “Organic” in their advertising yet they are not actually organic. It is buyer beware, as evidenced by the following email exchange with the makers of Aerify Plus, which used to use the term “organic soil conditioner” (see below).

The bottom line is that you should look for the USDA organic or OMRI-certified label on any fertilizers or amendments you plan to use on your organic land. Also look for a statement like this: ”Product certified by_____X_______", the name of the certifying agency such as MOSA, Oregon Tilth, OCIA, or any one of probably 50 other certifiers. Below are three examples of marketing claims that are misleading about whether or not they are certified organic.

Organic Soil Conditioner Marketing Examples - To be Organic or Not to be?

This is an email exchange with a company called Aerify Plus explaining if their product is in fact certified for use in organic operations.

From: Dantoin, Valerie L. Sent: Tuesday, October 12, 2024 4:45 PM

To: Stuart Franklin

Subject: Aerify Plus Question

I checked your FAQs and my question was not answered. Your product is advertised as Certified Organic.

Is this product Ok to use on certified organic soil?

What is the surfactant? That will probably determine if it qualifies as organic or not.

Thank you

____________________________________________________________________________________

From: Stuart Franklin [Email: Stuart Franklin] Sent: Tuesday, October 12, 2024 3:50 PM

To: Dantoin, Valerie L.

Subject: RE: Aerify Plus Question

The Aerify products are not certified for organic farms. The Surfactant is ammonium laureth sulfate. It does break down completely in the soil and a lot of organic gardeners have no problem using it, but none that are certified.

Figure \(\PageIndex{2}\): Aerify Plus label.

The old label called this an organic product. I revisited their website and saw that they have changed it to reflect that it is not organic. However, the website literature still says “organic gardeners know…..” You can see humic acids and kelp on the label–these are certainly organic ingredients if not sourced from an organic vendor, but probably are not certified organic. Find a label, examine it closely, and ask your certifier if you have questions about the product. Do not trust the salespeople – they do not know better and they may naively claim the product is organic.

Another example of a not-truly-organic amendment is Milorganite. This one even has “organic” built into its name. And I believe they say “organic” on the bag. It is bio-digested sewer solids from the water from the Milwaukee metropolitan sewage district. The issue here is that sewage sludge may contain trace heavy metals. Here is the website advertising for the soil amendment Milorganite. It is not certified organic. You cannot use this on organic farms or gardens. It is a cool, eco-friendly, recycled product as they claim, but still, it’s not organic.

Figure \(\PageIndex{3}\): The soil amendment Milorganite is made of bio-digested sewer solids, but it is not certified organic.