What is Essential for Plant Growth?

Several elements are essential for plant growth. However, 90% of the weight of a living plant is water, making oxygen and hydrogen the two most important elements needed in larger quantities for plant growth. Water is the most important element for plant growth, and without it, plants wouldn’t exist. Therefore, providing a plant with enough water is the most important step in growing a healthy plant.

According to studies, plant growth is dependent on about 17 different elements. The availability of each chemical element in the right proportion is responsible for healthy plant growth. If you are a gardener, or if you know your chemistry well, you must have some knowledge about these 17 essential elements for plant growth.

The nutrients facilitate the life cycle of the plant, 9 of them are very important and are required in large quantities, while the remaining seven are also essential, but a plant can survive without them. These 17 nutrients are classified into three categories, which are primary nutrients, secondary nutrients, and micronutrients.

The experts at American Biosystems have analyzed these three categories in detail below. Keep reading for more:

Primary Plant Nutrients

The primary nutrients that are essential for a plant to grow are nitrogen, phosphorus, and potassium. We will take a look at these nutrients in detail below:

Nitrogen for green leaves

Nitrogen is responsible for making the plant green. It’s a primary component of protein and is part of every living cell of the plant. Nitrogen is converted into amino acids inside the plant and is directly involved in photosynthesis. Therefore, nitrogen is the most important nutrient that promotes plant growth.

A plant lacking enough nitrogen causes light green or yellowish foliage and stunted growth. The yellow color will appear on both young and older leaves, and as time goes on, it becomes worse. However, nitrogen deficiency can be dealt with by using nitrogen fertilizers. These are very effective in helping the plant grow healthy and green.

Phosphorus for transferring energy

Phosphorus is responsible for transferring energy throughout the plant. Lack of enough phosphorus in the plant will result in carbohydrates manufactured in the leaves failing to travel to the flower or fruit. Phosphorus is essential for the growth of flowers, fruiting, and the storage of carbohydrates in the roots, tubers, and bulbs.

In most plants, phosphorus deficiency is hard to detect. However, in severe cases of deficiency, dead areas will be on the leaves, fruit, and stems. Older leaves are affected first before younger ones, and this is because phosphorus moves to the growing part of the plant.

Nitrogen is not mobile in the soil, and this makes it an easy nutrient to analyze in the lab. Avoid adding more if you find out that it has built up in the soil. If the growth is low, you can add more to the soil as needed.

Potassium for general health

Potassium is important for the photosynthesis process in the plant. It regulates cell turgidity, respiration, and water movement in the plant. The plant’s stomata are also controlled by potassium. When the plant has enough potassium, it is not easily affected by drought, it improves winter hardiness and crop quality. Potassium also increases disease resistance.

When there’s potassium deficiency, you’ll notice yellowing of the older leaves on the margin. Plants without enough potassium also grow slowly and have poorly developed root systems and weak stalks. This then results in lodging. By the time potassium deficiency is noticed, potassium fertilizers become of little value for the particular season.

Potassium is held by the soil’s cation exchange capacity as it is also taken by cation. Potassium is retained more in soils with high clay or organic matter because they have a higher cation exchange capacity which enables the process.

Secondary Plant Nutrients

The secondary plant nutrients that are essential for plant growth are calcium, magnesium, and sulfur. We will take a look at these nutrients in detail below for your better understanding:

Calcium

Calcium is responsible for stimulating root and leaf growth and development. It's responsible for producing elements that are part of cell walls and also strengthening the structure of the plant. Calcium produces several enzyme systems that neutralize organic acids in the plant. This then helps reduce plant nitrates.

The main sign of calcium deficiency is poor root growth. In serious cases, the plant stops growing and dies, because plants with calcium deficiency have roots that turn black and die. Young leaves and the growing points of shoots show the symptoms of calcium deficiency, and this is because calcium is not translocated in the plant like phosphorus, potassium, and nitrogen.

Magnesium

Magnesium is another important nutrient for plant growth. Since it is part of the chlorophyll molecule, magnesium is also actively involved in the photosynthesis process. It is also essential in phosphate metabolism and plant respiration.

Magnesium deficiencies appear on older leaves because it is translocated within the plant just like nitrogen, phosphorus, and potassium. If you see the older leaves of your plants turning yellow, bronze, or reddish while veins remain green, it is a sign of magnesium deficiency.

Liming your soil with dolomitic limestones prevents magnesium deficiencies in plants. When there’s an imbalance in other nutrients, it increases magnesium deficiency.

Sulfur

Just like nitrogen, sulfur is responsible for protein formation. This is because sulfur is an important component of three amino acids, which are methionine, cysteine, and cystine. The deficiency symptoms of sulfur are similar to those of nitrogen. Your plants will show a pale green color which will appear on younger leaves first.

After some time, the whole plant will have a pale green color. The deficiency usually takes place in plants that are planted in sandy soil in early spring. Sulfur can also be mineralized from soil organic matter. However, in cool soils, the mineralization process is slow.

Micronutrients

These are just as important as primary and secondary nutrients; however, they are only needed in smaller amounts. Micronutrients include boron, copper, iron, manganese, molybdenum, zinc, and chlorine.