What Do Plants Need to Grow? 4 Essentials You Can’t Skimp On

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Meta description: Do you know how to answer the question what do plants need to grow? If not, read this information to learn what plants need to survive and grow healthy.

The basics for all living creatures to survive on Earth is air, water, and food. These necessities are necessary for humans, animals, and plants. However, houseplants, since they are usually inside an office or house, have other needs as well to help them grow.

Sunlight, which is also an element that helps most animals, including humans, to grow healthy, is also necessary for plants. The information written below answers the question, what do plants need to grow? It can also teach readers the importance of plants to the world.

While it is essential to have the basics for survival, for plants to thrive, they need specific growing conditions that provide all the essentials they need. For instance, some houseplants need humidity while others don’t, but these nutrients are necessary for all plants to grow healthy.

Plant Nutrients

While animals and humans need to hunt for the food they need to survive, houseplants get what they need from the soil in which they grow. However, if the nutrients they need are not at adequate levels, then they will not be healthy and may not survive. 

Out of the many minerals, vitamins, and elements they require, there are six essential ones that houseplants must have, which includes:

  • Nitrogen
  • Potassium
  • Phosphorus 
  • Calcium
  • Magnesium
  • Sulfur

The first three nutrients on the list are those that plants need in abundance. This information about these nutrients will describe how they help plants to grow and be healthy.


The form of nitrogen that plants require is nitrate. This substance helps plant leaves grow strong so that their foliage develops. Foliage can keep the plant cooler, grow taller, and it aids in transpiration, which in turn helps develop rain for plants to grow. Having beautiful foliage lets owners know that their houseplants are healthy. 


This mineral helps plants grow during their early stages of life, so they become strong. It’s presence also increases the amount of protein in the plant and builds up the plant’s resistance to diseases and pests. Houseplants can get insects on them like aphids, fungus gnats, and red spider mites, but healthier plants are more resistant to them. Potassium also helps plants use water efficiently.


A plant is only as healthy as its roots, and if they are not healthy, then it can stunt their growth. Phosphorus not only makes roots grow strong, but it also assists in the development of seeds, flowers, and fruit. This element helps plants with environmental stress and allows outdoor plants to survive harsh winters.  

If a houseplant is deficient in phosphorus, most plant owners will be able to tell right away because the plant won’t look healthy. Its foliage may be smaller and sparser, and the color underneath the leaves may be yellowing or appear green with tinges of red, purple, or blue on the veins or stems. 


The mineral calcium aids in the structure of plants as it does the bones of humans. In plants, it works on plants’ cell walls to help them develop and grow correctly. Strong cell walls also help plants resist diseases. Calcium also assists plant metabolism and allows plants to take in nitrates, which is nitrogen.


Magnesium, which is a mineral, is essential in the photosynthesis process. Since it is a building block for chlorophyll, magnesium helps plants with their green coloring.


This yellow mineral stimulates seeds to grow and form properly. It also helps resist diseases by ensuring plants grow healthy by producing:

  • Amino Acids
  • Enzymes
  • Proteins
  • Vitamins

How Plants Use Oxygen

Another essential element for healthy plants is air or oxygen. As with humans, if they don’t have access to good quality oxygen, they can choke and die. One of the primary roles of air in the growth of plants is making the food they need to thrive.

In the process of photosynthesis, which is when plants use sunlight to synthesize food, they use the carbon dioxide, along with water, to create the starches and sugars that they feed on to stay alive. It’s crucial to recognize that over time, gases that are toxic to the plants can build-up when plants live indoors. 

Eventually, fresh air is used up in confined spaces, even if the area is large as a house. Then gases like ethylene and others form that can damage or kill the foliage on plants. Plants that live indoors can also accumulate debris on their leaves like dust, dirt, sprays from aerosol cans, and other substances.

The accumulation of these items on a plant’s leaves can interfere with exchanging gases, and it reduces the amount of light that a houseplant receives. To prevent the build-up of substances and to allow them to get more light, plant leaves need gentle dusting. Along with letting more light in and making processes like photosynthesis easier, the plants will also appear healthier.

Air and the Root System

Air is also necessary for having a healthy plant root system. Roots need air to help plants breath and remain healthy. If they don’t get the proper amount of air, then the roots can fail, which is a common problem for indoor plants.

If the roots fail, that keeps them from absorbing sufficient amounts of nutrients and water, the plants become stressed, and it can shorten their life spans. Some of the signs of oxygen deprivation are leaves that wilt or are smaller than usual, drooping plants, and chlorosis, which means a loss of the green color of the plant.  

It causes leaves to yellow or turn brown. A lack of air can also cause shortened life spans for the plants. They are also under stress when they don’t get the oxygen they need to thrive so that plants may be more susceptible to diseases and pest issues

How do Plants Use Sunlight?

To answer the question, what do plants need to grow? They need sunlight to grow and remain healthy. However, unless your home has lots of windows or faces south, getting enough light for your plants can be challenging.

The main reason that plants need sunlight is to feed themselves. During the process of photosynthesis, they absorb carbon dioxide from the air and use the water from the roots to form sugars and scratches with help from the sun. 

The chlorophyll in plants absorbs the sunlight, which stimulates the electrons within the plant ti form sugars and starches. These carbohydrates are what plants use for food. However, if they don’t have enough sunlight, then the plant can starve. 

Some plants thrive in low-light conditions, such as the plants that live on a forest’s floor several feet beneath the trees’ canopy. However,  green plants contain chlorophyll and need to undergo photosynthesis to survive.

If you don’t have good natural light coming into your home, consider setting up a grow light that simulates sunlight for the plants. You can also hang them outside during the day in the sunlight. Being outside will provide your houseplants with access to the sunlight that they need to create the food on which they survive.

How Water Helps Plants

The last essential need for houseplants to thrive is water. Plants need water because it strengthens their structures by filling the cells with water, which makes them stand straighter and look plumper. The cells of plants absorb water from rainfall or that which you give to your houseplants.

The structures become stronger because they are full of water that prevents the plants or leaves from drooping or wilting. Plants also contain cellulose, which helps with their structural support too. Water also keeps plants cooler and ensures the minerals they absorb get sent to the right places within their cellular network. This process is known as transpiration.

Transpiration is a process that benefits the plants and the Earth. During transpiration, after water evaporates within the plants, it passes through the stomata located on the underside of the plant’s leaves. It rises to the atmosphere and seeds the clouds, so when enough of it gathers, it returns to Earth in the form of rain. 

There are other elements, minerals, and processes that are necessary to grow healthy houseplants. The six nutrients from above, air, sunlight, and water are the essential elements that houseplants need for growth.

While fertilizers or better soils can help replace some of the missing nutrients if your plants are not healthy, they will not make up for a lack of sunlight, air, or water. By hanging your plants outside, you can make sure they get the air and sunshine they need to thrive, and you can supply the water they need as well. 

If you’re worried about the health of your plants, look for signs of problems, such as yellowing leaves, drooping stalks, or wilting and correct the issues causing the problems. With proper care, you can grow beautiful, vigorous, healthy plants by supplying their needs and knowing the answer to the question, what do plants need to grow?