Successful organic gardening begins and ends with good soil.  The organic gardener works with the soil to make sure it will produce abundant organic produce and flowers before and after every growing season. Organic garden fertilizers are added at least twice a year to enrich the soil and replace nutrients that the plants have used.

Organic garden fertilizers are not chemically manufactured and are generally made from live materials as the term organic implies. Organic gardeners may also add different organic or inorganic soil additives to control the acidity level or add micronutrients to the soil.  Common organic soil additives are epsom salts and potash.

The difference between organic garden fertilizer and soil additives is same as the difference between major nutrients and vitamins. Organic garden fertilizer improves the substance of the soil; whereas soil additives may help improve the consistency or to provide micronutrients.

Animal-based Organic Garden Fertilizer

Have you heard of manure? This is the most commonly used animal-based organic garden fertilizer compared to fish emulsion and others.  Usually, chicken manure, bat guano and cow manure are favorites, but you can also use horse and rabbit manure. In some places though, they even use composted human manure.

However, manure from predator animals, such as cats, is not allowed to use. Their digestive systems contain bacteria that are pathogenic to humans, and the bacteria can get into or on food grown in soil fertilized with their feces. Before it can be used as an organic garden fertilizer, all manure should be composted first. This removes E. coli and other potentially dangerous pathogens and it can be added to the soil in either a solid or liquid form, and should be mixed well into the soil. Manure should be added to the soil at least several weeks before planting to allow it to age and mix with the soil—and to make the gardening experience more pleasant.

Plant-based Organic Garden Fertilizer

The most common plant-based organic garden fertilizers are seaweed, compost, worm castings and “green manure”. Seaweed and kelp are usually purchased as dried and processed organic garden fertilizer.  
Making compost for organic garden fertilizer is a continuing process.  The process of doing it is can be learned from different community workshops or other experts.  It is an excellent way to recycle vegetable matter, such as peelings and scraps. 

Worm castings—or worm composting—are very rich in nutrients and can be either purchased or made. To make worm castings, the need to know the right kinds of worms to use is important. You can get these worms from any organic gardening source, a covered tub of some kind, and slightly damp vegetable matter or even old newspapers.

“Green manure” is planted as a cover crop, usually in the fall after harvest.  A nitrogen-fixing crop, such as soybeans is planted most of the time. When the cover crop emerges in the spring, you dig it into the ground, allowing the plants to decompose and enrich the nutrients of the soil.

You will be adding natural, living matter to the soil whether your organic garden fertilizer is purchased or owned. You will also be preventing the chemical runoff that happens with chemical fertilizers.  And you’ll be enriching your soil, which is the source of life for your garden.