Environmentally Friendly Fertilizers

  • Difficulty Rating: Beginner
Environmentally Friendly Fertilizers

Feed the soil, and let the soil feed the plants.

It’s a mantra I live by in my garden and so do many other gardeners that really “get” the importance of having healthy soil and how important that is to having a bountiful and productive garden. But you can’t feed the soil with man-made, synthetic chemicals. Although they are very effective at supplying nutrients to the plant, they do nothing to improve the soil and actually have an adverse impact there. That’s not the way I want to garden.

Classic ‘organic’ or natural fertilizers and amendments include compost and manures of various types. These are some of the oldest and most time-tested choices for improving the conditions of soil naturally. But now in the twenty-first century, you’re ready to expand your horizons as to eco-friendlier choices but you’re as confused as the next guy when it comes to actually knowing what nutrients to buy and still be sustainable. The choices seemed unlimited.

With the realistic possibility of feeling overwhelmed, allow me to explain some of the differences between organic and synthetic (non-organic) choices, review a few fertilizer basics, and then offer some viable organic or natural alternatives to non-organic products.

Organic vs. non-organic

All plants receive their nutrients in chemical form. It may surprise you to know that they cannot distinguish between how the nutrient was derived, whether organic or non-organic.

Organic nutrients, when referring to plant nutrition, generally refer to any fertilizer, which is derived from plant, animal or mineral origin. It must have one or more essential nutrients for plant growth along with the presence of carbon. Organic nutrients must first be broken down and digested by soil microorganisms that then release these nutrients in a form available to plants.

This process also produces humus, a vital ingredient to improving soil structure. As part of this structure, organically derived nutrients are very resistant to leeching and contain a very low salt index. The net result is nutrients that remain in the soil until utilized by plants and little risk of burning or dehydration, even in periods of extreme drought or over application.

Non-organic fertilizers (also known as synthetic or manufactured) are produced chemically. In the classic sense, they are made to deliver nutrients rapidly, such as those that are water-soluble, or over time as a controlled release.

Although very effective for providing rapid or prolonged periods of feeding, these have a high salt index. The potential risk to plants and the soil food web is burning and dehydration along with the leeching of unabsorbed chemicals into waterways.

Fertilizer Basics

Based on what you are trying to achieve for your plant’s growing success will determine which fertilizer to buy. Any fertilizer package prominently lists three numbers. These are the primary nutrients that are needed in the greatest quantity by plants. These numbers represent the percentage of nitrogen (N), phosphorus (P) and potassium (K) found in each package.

Nitrogen is primarily responsible for vigorous growth and dark green color. Phosphorus plays a major role in the root development and flowering. Potassium is mainly responsible for disease resistance and the overall hardiness of the plant.

Organic and Natural Alternatives

Synthetic fertilizers are usually listed simply by these numbers referenced above, since they are manufactured chemicals. Organic and natural alternatives however are often listed primarily by what they actually are, such as blood or bone meal or fish emulsion.

But somewhere on that package, you’ll find those all important three numbers which is the key to knowing what role that product will play in your garden. Here is a partial listing of the most commonly available organic and natural fertilizer alternatives, sorted by their role for providing nitrogen, phosphorus or potassium.

Nitrogen: Dried blood, blood meal, cottonseed meal, fish emulsion and seaweed extract

Phosphorus: Bone meal, rock phosphate

Potassium: greensand, sulfate of potash

In addition to the three primary nutrients, there are 12 other elements considered essential for plant growth that are absorbed from the surrounding soil. Organic and natural soil amendments are a readily available way to provide all of these elements as well.

I rely on these natural amendments to ensure I’m feeding the soil, which in turn feeds the plants. I find that to be a safe, effective and environmentally responsible approach to gardening. And I love knowing that as I feed my plants with natural solutions, I’m creating a healthier garden and making a small but important step in my role to help grow a greener world too!