Want to keep your garden healthy without having to use chemically processed synthetic fertilizers?  Fortunately, there are a variety of organic garden fertilizer options to help your garden thrive. Organic fertilizers come from natural plant or animal sources, while their inorganic, or synthetic, counterparts go through a manufacturing process and can contain harsh chemicals or impurities of toxic heavy metals like boron, copper, cadmium, or zinc.

Why choose an organic garden fertilizer?

The most poisonous ingredients found in many fertilizers are nitrates and nitrites. Nitrate inhibits the ability of blood to carry oxygen to tissues, it’s breakdown products are carcinogenic, and it can alter thyroid function.[1] Humans are mainly exposed to nitrates through drinking water contaminated by man-made nitrogen fertilizers. Drinking water contaminated with nitrate is a large public health problem and is associated with increased cancer risk.[2] Even exposure at home by ingesting an inorganic nitrogen fertilizer can result in dangerous symptoms like fainting, low blood pressure, or seizures, and touching large quantities can cause severe burning of the skin.[3]

Organic health benefits

The organic farming movement is growing in the United States and organically grown food can increasingly be found at grocery stores and farmer’s markets. Laboratory studies have found health benefits of consuming organically produced food versus conventionally grown food. These health benefits are likely due to a variety of factors, including the absence of pesticide residues and heavy metals, and higher levels of vitamin C and phenolic compounds.[4] So why expose your family to the dangers of synthetic fertilizers when there are many options for safe, healthy, organically grown gardens?

All-natural fertilizer options for your garden

Fertilizers usually provide nitrogen, phosphorous, and potassium to your plants. There are many natural sources of these vital nutrients for your garden. When choosing a store-bought product, be sure it is labeled organic and read the ingredients to be sure you know what you are putting in your garden.

1. Compost. Decomposed organic matter is by far the easiest and best way to build healthy soil. Make your own or buy organic compost. Incorporate large amounts into your garden bed before planting or pile around your established plants.

2. Bone meal is made from steamed animal bones ground into a powder. It breaks down slowly, providing your plants with a slow, steady dose of calcium and potassium. Sprinkle 2 tablespoons into a hole before planting.

3. Fish fertilizer is made from fish remains. It can be bought in a liquid form, which should be diluted in water then poured over established plants, or a dried meal, which can be incorporated into soil before planting. Warning: this type of fertilizer can have a pungent fish smell.

4. Alfalfa meal is full of nutrients for your flowering plants to help boost blooms. It can be sprinkled around the base of each plant, or into a hole before putting in a new planting, and should be used repeatedly for those plants that bloom all season long.

5. DIY compost tea. An easy make-at-home fertilizer is made from converting compost into liquid form. Here’s how to make your own:

• Fill a five-gallon bucket one-third full with organic compost, then fill almost to the top with water (use rain water or filtered water to avoid chemicals from the city water).
• Let the bucket sit out for about a week, stirring the contents a few times a day.
• Strain with mesh, such as a burlap sack, and collect your compost tea.
• Pour over established plants as often as every 2 weeks.

Share your experience

What do you use to naturally fertilize your garden? Share your gardening tips in the comments section below.

[1] Rev Environ Health. 2009 Oct-Dec;24(4):357-63.

[2] J Environ Public Health. 2013;2013:603468.

[3] National Institute of Health. Medline Plus: Plant Fertilizer Poisoning.

[4] Int J Environ Res Public Health. 2014 Apr 8;11(4):3870-93.