Build Better Garden Soil With Free Organic Fertilizers!

Avoid high fertilizer costs — here are your best organic fertilizers, including two that you won’t even have to pay for! Build better garden soil using organic fertilizers found in your very own backyard.

| April/May 2008


You can build better garden soil by applying the right types and amounts of organic fertilizers.

Photo by Barbara Pleasant

The information in this article was reviewed and updated in January 2015. —MOTHER EARTH NEWS

As more and more people recognize the many benefits of organic gardening methods, a fresh crop of organic fertilizers are sprouting on store shelves. Many are overpriced, and some are stunning rip-offs that reputable stores and catalogs should be ashamed to sell. The really amazing thing is that two of the best organic fertilizers are easily available to most of us absolutely free! (See below) It’s definitely a buyer-beware world out there. If you’re not careful, you could pay five, 10 or 4,000 times more than necessary to get the nitrogen and other nutrients you need. Here's what we found when we evaluated the pricing for 21 fertilizers:

The Best Free Fertilizers

All products labeled as “fertilizer” must be labeled with their content of the three major plant nutrients — nitrogen, phosphorous and potassium (N-P-K). Most organic fertilizers are bulkier than synthetic chemical products, so their N-P-K percentages are typically lower than synthetic products, and their application rates are higher.

Also, because organic products are biologically active, their N-P-K numbers may change somewhat from batch to batch and over time. Because of this, it can be hard for producers to comply with the labeling laws. As a result, some excellent organic fertilizer options, such as compost, often are not even labeled as a “fertilizer.” One of the best free fertilizers, grass clippings, break down so quickly that they can’t be bagged and sold.

But make no mistake, compost and grass clippings do what fertilizers are supposed to do: They enrich the garden soil with nutrients that plants and microscopic soil life-forms are eager to use. In most areas, you can easily collect grass clippings from your neighborhood, bagged and set out ready to bring home. And many communities make yardwaste compost (made mainly from grass clippings and leaves) available for free.

So, if you can get free clippings or compost, how much should you use? Here are guidelines prepared with help from soil scientists at Woods End Laboratory in Maine.

6/10/2016 10:41:05 PM

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10/8/2015 8:57:44 AM

Hi: Had a quick question. As a vegetarian I am not particularly keen to use fertilizers with meat or fish meal in it. Which of the bought fertilizers that you assess would work but not have anything more than manure? (animal waste product seems fine to me :)) Thx Chitra

5/12/2015 6:00:13 PM

I'm surprised that your coffee pot, local Starbucks or some other coffee shops as an avenue for free bags of used coffee grinds. I grab a bag whenever they're available and use them in potting mixes, the compost bin or by blending it directly into the garden soil.

5/11/2015 12:17:24 AM

Organic fertilizers are quite essential for our soil and it helps to improve the value of soil and also helps to protect the crops. Apart from chemical fertilizer most of the gardeners are always choose organic fertilizer which is really suitable for plants and crops. Organic fertilizer and organic foods are really beneficial for human being and therefore we should promote the use of organic products in order to improve our health and hazards.

catherine banks
5/11/2012 10:46:59 AM

I love this article! I love that it is possible to use things that would normally go to the trash to grow my garden.

4/25/2012 1:34:56 AM

I was thinking the same thing as Kim Krupsha. Using the term "organic" and then advising people to utilize lawn clippings and municipal compost is a bit misguided. There's no way to know what chemicals have been used on these materials and while they may be organic in origin, they are no way considered organic as in Certified Organic. It's like using the common buzzword "natural" to describe something - it means nothing.

kim krupsha
4/23/2012 3:18:01 AM

I'm concerned that the advice to use free local municipal compost is misguided. With the prolific use of commercial and home-use lawn fertilizer and herbicides and pesticides, local municipal compost may be chock full of hazardous chemicals. These are not things you want on your vegetables!

boyd craven
2/21/2012 5:32:25 AM

Get a rabbit or two. Whether pet rabbit or meat rabbit, their "bunny berries" (manure) makes an excellent cold fertilizer or "tea" that can go directly to your plants without fear of burning them. I have a page on facebook called The Urban Rabbit Project where we provide information on the subject.

4/18/2009 6:35:28 AM

We live on the coast of Maine (actually an island!) and find that SEAWEED makes an ideal free fertilizer for our gardens. I mulch with it, making sure it doesn't come in contact with my plants because it retains a lot of moisture and can cause rotting. When it dries out, I walk across it, breaking it down into the soil. Even after it has broken down, it holds water after a heavy rain, keeping the soil moist, reducing the need to water.

garden goddess
2/15/2009 10:36:38 PM

Reading all of the info on the fertilizer, I have chickens and thus a lot of chicken manure, and i know it is hot and has a lot of ammonia, but could i burn it and put it in the garden as bio ash, how would that work, well i think i will try it, also can i add ash from the fireplace? Sometimes i mix it in to my compost pile, or spread it under the pecan trees, they seem to like it. I made chicken poo tea, and put some on my strawberry's it seemed to help them bloom and made some great berries, but burnt a little of the leaves, guess i need to dilute it a little more.

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