sources of phosphorus

Plants require three macronutrients. The compounds needed in large amounts by an organism that typically come from the soil: nitrogen, phosphorus, and potassium. Each has a different role to play in the healthy development of plants, and various compounds, materials, and mixtures can be added to soil to bolster its nutrients.

In the case of phosphorus, these include commercial fertilizers, which can include rock phosphate or bone meal or other materials like hair, the waste from some shellfish, urine, etc.

Some of these sources of phosphorus have a long history of human use, while others have been created relatively recently. Similarly, some of them occur naturally, while others come from commercial and scientific developments.

As such, gardeners have a series of options to choose from when looking for a source of phosphorus for their gardens. However, phosphorus is a limited resource on the Earth, and too much of it can hurt both the plants and the environment.

Natural Sources of Phosphorus

#1. Phosphorus (From Urine)

As gross as it might sound, urine from humans and other animals contains some of the macronutrients plants need to thrive. It has been used to fertilize different crops, though it mainly finds use in gardens. Primarily, this is because the cost of transporting urine in high volumes is prohibitive not to mention getting the urine in the first place involves some unpleasant logistics.

It also smells bad and can contain pathogens and the residue of pharmaceutical drugs, which can harm the plants it was intended to help. For use in crops, the phosphorus is extracted from the urine, which can be done for nitrogen as well.

However, in a garden, urine can be used to help plants and trees grow. A few considerations must be taken, however. For one, urine also contains nitrogen, which can cause “burns” on smaller plants. Those yellow splotches in yards where dogs have urinated are an example of this, so direct urinating on plants should be avoided. Trees can weather this off-kilter method of providing phosphorus.

Similarly, most municipalities have laws that might prohibit urinating in the open, even on private property – check with your municipal bylaws prior to urinating on your garden, or pee in a cup and spread it manually.

Besides human urine, there are many naturally occurring sources of phosphorus that can be used in the garden, including bat guano (or feces), bone meal, crab and shrimp waste, burned cucumber skins, hair, and mushroom compost.

The nutritional value of these sources can vary a great deal. Numerous factors can also vary the nutrient levels within each source, raw bone meal can have between 15 and 27 percent phosphorus, for example. Age, decomposition rate, method of application, exposure to rain or sun, the type of soil it’s applied to, and the number of microorganisms present all of these changes the percentages of each nutrient available.

Most often in terms of naturally occurring organic sources of nutrients, farmers use manure or bone meal to give their crops not only phosphorus but also nitrogen and potassium.

#2. Phosphate Rocks (as a Plant Food)

Phosphate is a mixture of phosphorus and calcium. It is mined around the world, including the United States. Each source has a slightly different chemical composition. It is important to note that this source of phosphorus cannot be used in soils with a pH above 7 (basic soils).

This form of phosphorus has some advantages over other sources. Compared to, for example, bone meal, it’s cost-effective. It also contains other nutrients including calcium and magnesium. It also comes with a set of downsides, however.

Runoff from agriculture operations and gardens can also reach water systems, which can cause a serious threat to lakes. The added phosphorus can induce algal blooms, which lower oxygen levels in a body of water, which, in turn, can kill many of the living, aquatic organizations in it.

Though rock phosphate occurs naturally, it’s a non-renewable resource, and overusing it will deplete a region’s stores of it. In fact, according to some researchers, the world has between 500 and 600 years’ worth of it left.

Plants get phosphorus from the soil. Farmers add phosphorus to soil, usually in the form of synthetic fertilizer or livestock manure, to replace what is removed when the plants grow and are harvested for human food or animal feed.

#3. Bones

Even though they did not know that bones were rich in phosphorus, farmers in places such as China and Wales recognized the benefits of using bones as a source of fertilizer many centuries ago. By the 1700s and 1800s, countries such as England recognized the fertility value of bones.

They began to import human and other animal bones on a large scale from around the world. However, after the sources of these bones were depleted, the bone business failed to persist as a major source of phosphorus for food production.

#4. Recycled phosphorus from digested feed and food

Currently, a large portion of the phosphorus that’s fed to livestock or poultry is recycled back into the food system in the form of manure. Researchers are also looking for other ways to retrieve and reuse phosphorus from dairy farms. However, very little phosphorus is recycled after human consumption. Instead, most of the phosphorus that’s used for human food production comes from rock phosphate.

#5. Rock Phosphate

Solid rock phosphate isn’t itself a good fertilizer. The rocks contain a form of calcium phosphate in which the calcium and phosphorus bind tightly, making it difficult for rock phosphate to dissolve in soil. This means that plants can’t easily take up that phosphorus to improve their health and growth.

Functions & Roles Phosphorus Play In Plant’s Growth

The impact of phosphorus in plants cannot be understated. The macronutrient exists in the nucleic acids of a plant’s DNA, so it plays an important role in reproduction, which, in the case of crops, can increase the yield, quality, and rate at which the crops mature. Similarly, phosphorus increases stalk strength and help roots grow.

Phosphorus is needed for root development, stem formation, and fruitings in summer vegetables like tomatoes, peppers, eggplants, squash, melons, and cucumbers.

Phosphorus tends to be widely disbursed in soil, so it’s hard for these plants to get enough of it within their limited root zones. To get enough phosphorus to produce fruit, fruiting plants evolved symbiotic relationships with mycorrhizal fungi. Almost all plants that bear fruit form mycorrhizal associations.

Too much phosphorus can also harm the plants it was meant to help as well as the nearby environment. High levels of phosphorus can hurt the growth of soil organisms called mycorrhizal fungi, which form a symbiotic relationship with the plants at the roots. Phosphorus may also not be necessary for every situation and in every soil.

Grass, for example, doesn’t produce large flowers or fruit, so the phosphorus present in the soil should be sufficient. Too much fertilizer and, thus, phosphorus can cause burns on smaller plants like grass.

Unfortunately, phosphorus appears in low levels in agricultural soil in which it is used regularly or leached away; most normal soils contain it in levels suitable enough to grow plants. Low soil levels of phosphorus can cause reduced growth, lowers crop yield, and a slower rate of maturity.

Younger plants can take on a purple tint on their leaves. Humans have used phosphorus as fertilizer for more than 100 years; initially, farmers and gardeners used ground bone, and, more recently, the element is created through chemical reactions.

Leave a Comment

Your email address will not be published.

error: Content is protected !!