While plants are capable of converting sunlight, air and water into usable energy through photosynthesis, they also require other ingredients to build healthy plant tissues, flowers, and seeds – we call these essential plant nutrient elements. They’re called essential because a plant can’t grow properly or survive long without them. Essential plant nutrient elements can be broken into three categories. Let’s look at the three categories of essential plant nutrients and what elements belong in each category.
Primary Plant Nutrients
There are six primary nutrient elements required by plants for normal cellular activity and growth:
- Hydrogen: Hydrogen atoms are supplied to plants through water molecules taken up by the roots that are then split in the leaves during photosynthesis.
- Carbon: Carbon is supplied to the plant from atmospheric carbon dioxide taken in through the leaves and is an essential element for photosynthesis.
- Oxygen: Oxygen is supplied to the plant from both water and air and is essential for aerobic processes.
- Nitrogen: Nitrogen is required by plants to produce proteins used for tissue growth.
- Phosphorus: Phosphorus is required by plants for proper root formation, bud and flower setting and increasing seed size.
- Potassium: Potassium serves several functions in plants, including aiding in carbohydrate production, metabolic regulation, and disease resistance.
Secondary Plant Nutrients
Although the term secondary plant nutrients may sound like these nutrients are less important than primary plant nutrients, they are just as important, but needed in smaller amounts than primary plant nutrients. There are three secondary plant nutrients:
- Calcium: Calcium plays an important role in the growth and development of healthy plants. It is essential for cell membrane formation and neutralizing toxins in the plant. Calcium also helps to bind inorganic and organic particles together in the soil.
- Magnesium: Magnesium is essential for photosynthesis. Plants would not be able to perform photosynthesis with out it.
- Sulfur: Sulfur is essential in the production of many proteins in plants.
Micronutrients
Micronutrients doesn’t mean the nutrients themselves are smaller in size, it just means that plants only require tiny amounts of them for normal, healthy development and reproduction. There are seven elements that are considered micronutrients for plants:
- Boron
- Chlorine
- Copper
- Iron
- Manganese
- Molybdenum
- Zinc
Organic and Synthetic Plant Fertilizers
Most non-cultivated plants rely on natural fertilizers like decayed organic matter from fallen leaves, tree limbs, and other decaying organic materials, while most commercially grown plants rely on synthetic fertilizers that are often derived from man-made chemical processes. Microorganisms living in the soil help to break down organic matter, releasing nutrients back into the soil, which are taken up by the roots of living plants. Other organisms in the soil like earthworms can also transform raw materials in the soil into useable forms of nutrients. Synthetic fertilizers are often applied to the surface of the soil either in a granular form or in a liquid solution. Synthetic fertilizers can also be applied directly on the leaves of plants in a liquid solution (foliar feeding).
Organic fertilizers usually release nutrients slowly over time as microorganism work to break down the organic matter and release nutrients into the soil. Synthetic fertilizers on the other hand have readily available nutrients that can be taken up by the roots quickly. Too much synthetic fertilizer can cause damage to plants, known as burning.
Fertilizers and Soil pH
Soil pH is critical to nutrient uptake by the roots of plants. If the pH level is too high or too low, some nutrients will not be absorbed, and the plant will not develop or maintain itself properly. Most plants prefer soil pH in the range of 6.0 to 7.0, which is within the neutral range. However, there are some plants that prefer soils with a pH level that is either slightly acidic or slightly alkaline. Soils tests are the best way to determine the pH level of the soil in which you would like to grow plants in.