What Do Your Plants Need? Soil Nutrients Explained

Your soil is your lifeline to a healthy garden. Without the right nutrients, in your soil, your garden will not produce as much as it should. Your plants need certain elements so that they can grow, reproduce and make fruits, flowers, and vegetables.

The first step in providing your plants with the right diet is to know what nutrients will make them healthy. The second step is knowing what happens if they do not get those nutrients. The third step is making your soil more compatible with your plant’s needs.

This article will give you a rundown of the necessary ingredients that you need in your soil to help your plants thrive and what deficiencies look like.

A garden with great soil fertility is going to surpass all others in terms of plant health and production. One that is rich in the proper nutrients is going to give you abundant amounts of vegetables to eat fresh and can for winter.

So let’s get started!

What Do Plants Need From The Soil To Grow?

Just like you need vitamins and minerals for your body, so do plants.

Animals including humans have a big advantage over plants. We can move. If I need food I go to the garden, pick what I want to eat and then go into the kitchen to prepare it. I can choose healthy foods that will nourish my body. (I can also go to the grocery store to get unhealthy choices but we won’t focus on that!)

Plants stay in one place but they still need to access what they need. Plants get what they need from the soil and the air around them. We have limited control over the sun and the wind. We have a lot of control over what is in our garden soil.

Nutrients = Fertility

Since plants can’t move we need to know what they need to be healthy.

They can grow roots to try to reach more nutrients but they are dependent on what is available in their space. It is our job to make sure their space is overflowing with goodness.By goodness, I mean macro and micronutrients.


Macronutrients are the major nutrients that all plants need to survive. They are nitrogen(N), phosphorus (P), potassium (K), calcium(Ca), magnesium (Mg) and sulfur(S). Your plants simply can not survive without these nutrients.

The Big Three – NPK

Each letter represents an element from the periodic table.

Nitrogen (N)

Phosphorus (P)

Potassium (K)

You see those letters listed on fertilizers and plant growing guides. Manufactures put these letters on the bags to tell you how much of each element the fertilizer contains. For instance, my favorite goto fertilizer for my organic garden is Alaska Fish Emulsion. You can see that the numbers on the container say 5-1-1. That means that there are five percent nitrogen, one percent phosphorus and one percent potassium per the mixing instructions.

My GoTo fertilizer

You may have seen fertilizers that include 10-10-10. These are typically commercial fertilizers. Most organic fertilizers come from natural sources, in this case, scrap from the fishing industry, and have lower percentages. This is perfectly OK. If you are wondering why I think organic is the best way to grow your crops, check out my article 10 Reasons To Eat Organic - the short and long version

This chart tells you why you need each nutrient and what happens if your plants do not get an adequate amount

The Big Three - macronutrients that your plant needs for survival.

The Big Three - macronutrients that your plant needs for survival.

The Other Big Three

We don’t talk about them as much but these next three are very important. One of our favorite vegetables, tomatoes, suffers from blossom end rot. Blossom end rot is caused by a calcium imbalance.


Magnesium (Mg)


Macronutrients like Calcium are very important for your plants.

Macronutrients like Calcium are very important for your plants.


Micronutrients are elements that plants must have to grow and be healthy. Sometimes people think that because the plant needs less of something then it is not always necessary. Micronutrients are necessary, just in smaller amounts. A deficiency of any one of them, can cause real problems for your plants.


  • iron (Fe) 

  • boron (B) 

  • chlorine (Cl)

  • manganese (Mn)

  • zinc (Zn) 

  • copper (Cu)

  • molybdenum (Mo)

  • nickel (Ni)

Micronutrients are vital for plants

Micronutrients are vital for plants

Plants only need small amounts of these nutrients but they do big jobs

Plants only need small amounts of these nutrients but they do big jobs

Elements From The Atmosphere

Plants (again, just like us) require elements that are naturally occurring in our atmosphere. Many botanists would also include Carbon (C), Hydrogen(H), and Oxygen(O) as necessary macronutrients.  They are the building blocks for your plant and come from air and water.

We are going to look at them a bit differently since they are not something we can control as easily.

Carbon, hydrogen and oxygen are the most abundant elements found in plants. They are also responsible for the important task of photosynthesis.

Hydrogen is typically found in water and is essential to the plants growth. We can control this one by adding water if the weather is dry. However its harder to remove water when we have too much rain.

Carbon comes from CO2 in the atmosphere and is essential for food and energy.

Oxygen is necessary for cellular respiration in plants. During photosynthesis the plant breaks down CO2 and uses some of the oxygen for energy. Excess oxygen is released into the air. Lucky us!

During photosynthesis the plants uses carbon dioxide and water to sugars, carbohydrates and proteins for the plant.

Here is a great visual to help you see what plant deficiencies look like.

Credit: Big Picture Agriculture

Credit: Big Picture Agriculture

Don’t treat your soil like dirt!

The best way to analyze your soil is by doing a soil test. Read my article Pass the Test: Soil Testing For Improved Fertility (coming out 9/18/19)

Are you a gardener, homesteader or DIY enthusiast. Then you will want to check out one of my favorite stores Lehmans Hardware. Click on the link below and check out their gardening tools and more.

Fall Cleanup Made Easy with Hand Forged Axes at Lehman's!

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Author, Ame Vanorio is a freelance writer and director of Fox Run Environmental Education Center. She teaches classes locally and online about organic gardening, green building and wildlife conservation. Ame is a licensed wildlife rehabilitator. She lives off grid on her Kentucky farm with a myriad of domestic and wild animals.