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Phosphorus is a vital nutrient for plants, and is crucial to ensure healthy plant growth. But it’s not always easy to find phosphorus or ensure your plants get enough of it. Learn where you can find sources of phosphorus for plants both inside the home and outdoors.

Plants get phosphorus from the soil, but farmers need to add phosphorus to the soil in the form of synthetic fertilizer or livestock manure to replace what plants take out when they grow and are harvested for human food or animal feed.

If you are growing your own plants, providing them with enough phosphorus is crucial to ensure they can harvest the sun’s energy and grow well. Read on to learn about the importance of phosphorus to plants, and how to provide your plants with the phosphorus they need.

Sources of phosphorus for plants

Phosphorus plays an important role in photosynthesis and helps in the formation of cell membranes, sugars, and proteins.

Phosphorus is an essential nutrient for plants, and it can be found in a variety of soil types.

Phosphorus gets into plants’ tissues through their roots, which absorb it from the soil. 

The amount of phosphorus in the soil depends on how much phosphorus has previously been added by fertilizers or organic sources like animal manure or compost.

Learn how soil helps plants

The best type of soil for phosphorus is one that is rich in organic matter, or material from living or once-living organisms. 

This is because organic matter contains phosphorus that has been released from the organisms as they grew and died. 

The organic matter decomposes into other forms of nutrients for your plants, including carbon dioxide and water (which the plant uses to grow).

Another source of phosphorus is rock phosphate. 

Rock phosphate is a type of ore that contains high levels of phosphorus and other minerals such as calcium and potassium. 

It can be mined and processed into fertilizer pellets that can be added to your garden to increase its overall fertility level.

Calcium polyphosphate is another source of phosphorus, which comes from mineral rocks like dolomite and limestone. 

This form of phosphorus is also used as a fertilizer and has many benefits for your lawn and garden.

Organic sources of phosphorus for soil

There are many organic sources of phosphorus for soil, including bone meal and compost.

Phosphorus comes from organic sources—meaning stuff that was once alive, like plants and animals—in the form of phosphates. 

When you add these organic sources to soil, it releases phosphates into the ground where they can be absorbed by plants. 

This process helps create a thriving ecosystem in your garden and ensures that your plants have all the nutrients they need to grow healthily. 

One of the best ways to increase the amount of phosphorus in your soil is through composting. 

Composting releases beneficial microorganisms into the soil that help break down organic matter into a form that can be easily used by plants.

Another way to increase the amount of phosphorus in your soil is by adding organic fertilizers such as bone meal or alfalfa meal into your garden bed before planting. 

These fertilizers release nutrients slowly over time so that plants do not get overwhelmed with too much at once. 

Learn how to make compost

How much phosphorus do plants need? 

The amount of phosphorus plants need depends on the type of plant. 

Most annual plants need large amounts of phosphorus as they begin to grow.  

Some plants, like beans and legumes, need a lot of phosphorus. 

Other plants, including most house plants, don’t need much phosphorus at all.

You must be careful however not to apply too much phosphorus to the soil.  

The buildup of phosphorus in lawns, gardens, and pastures can cause plants to grow poorly and even die. 

High phosphorus levels can lead to a deficiency of micronutrients such as iron and zinc in the soil. 

Household sources of phosphorus for plants

There are many household sources of phosphorus that can be used for plants, including bone meal and egg shells. 

Did you know that there are several items in your home that can be used as sources of phosphorus for plants? 

Many plants require phosphorus in the soil to produce flowers and fruit, but it’s not always easy to find a source. 

Here are some household items you can use:


Eggshells are high in calcium, which is good for your garden, but they also contain phosphorus, which is essential for healthy plant growth. 

Eggshells that are crushed into small pieces add a nice texture to soil that’s already been broken up by worms or other critters living in the soil (which is why they’re often used as fertilizer).

Learn how to improve your soil with eggshells

Coffee grounds

Coffee grounds are another great option for providing phosphorus to your plants. 

They contain more nutrients than most other types of waste from the kitchen, making them an excellent choice for fertilizing your garden or lawn. 

Just sprinkle them around the base of any plant and watch it grow!

Fruit peels

Fruit peels are another good source of phosphorus for your plants and they contain high levels of nutrients like potassium, magnesium and calcium which will help strengthen their roots as well as keep pests away from their leaves

Bones & meat scraps

Bones and meat scraps are high in phosphorus, but they can also be tough to digest and might not be safe for dogs or cats.

If you’re using bones from a butcher shop or farm animal, make sure they’ve been cleaned of bacteria and other contaminants before using them.

How to add phosphorus for plants

Phosphorus is an essential plant nutrient, and you can add it to your soil by adding bonemeal or rock phosphate. 

If you’re growing a vegetable garden, you’ll want to add phosphorus to the soil in the spring, when plants are starting their growth cycle. 

You can also add phosphorus to your lawn in the fall to help your grass grow strong over winter.

The best way to add phosphorus to your soil is by adding compost or manure, which contains organic matter that decomposes over time and releases phosphorus into the soil. 

You can also purchase a fertilizer that contains phosphorus from your local gardening supply store.

You can add phosphorus to your soil by mixing in rock phosphate or colloidal phosphate, which is made from ground-up rocks.

You can also add phosphorus by adding bone meal to your soil. 

Bone meal contains phosphorus and nitrogen, which are both essential to plant growth. 

Bone meal also contains calcium, which helps prevent deficiencies in plants such as root rot or blossom-end rot.

What does phosphorus do for plants?

Phosphorus is an essential element for plants to grow and thrive. It is a component of DNA, the genetic material of all living things. 

Plants use phosphorus to build proteins, which are used in everything from photosynthesis to cell membranes.

When plants absorb phosphorus, they store it in their roots.

This allows them to create new cells and grow throughout their life cycle. 

If a plant doesn’t have enough phosphorus, it will not be able to produce enough energy or grow as large as it would normally be able to.

Phosphorus is an essential element in the creation of ATP, or adenosine triphosphate, which is the energy source that drives all of your body’s functions. 

The phosphorus in ATP is what makes it so important for plants to be able to grow and thrive.

Final thoughts

Phosphorus is an essential mineral for plant growth. It’s a major component of DNA and RNA, so it’s crucial to cells’ ability to grow and reproduce. Finding a good source of phosphorus for your plants will help ensure they thrive. 

Greg Volente

Greg Volente holds a Naturalist Certificate from the Morton Arboretum, worked for The Nature Conservancy leading environmental education programs and doing natural areas restoration, and worked in the soil science research & testing lab at Michigan State University. Besides gardening, he's an avid wildflower enthusiast, and loves botanizing, hiking, and backpacking.