Fertilizer and Plant Nutrients
One of the most important things to understand when growing plants is the impact of nutrients and fertilizer on plants. This understanding will allow you to make the right decisions about feeding your plants and to get the results you desire. Their are 17 nutrients that plant scientists have discovered as the most important. This post will go through what different nutrients do to plants and how you can utilize them with your plants.
Fertilizer: The Big Three Nutrients
For plants there are three nutrients that you see most commonly on fertilizer or grow solution packaging. Those are nitrogen, phosphorous, and potassium. Generally speaking you will see them listed in the order of Nitrogen, Phosphorous, and Potassium. See the label below as an example;
These are the 3 main nutrients for plants and are needed in the highest quantity by plants. You might see it listed as NPK, which are the chemical symbols for those plants. The do the following as follows:
- Nitrogen:It is important for the structure of, It is a building block in amino acids. Nitrogen is involved in metabolic processes in the molecule NADP and NADH. It is important for protein and enzyme synthesis. Without nitrogen there is not protein! Nitrogen is generally higher in vegetative fertilizers.
- Phosphorous: a component of DNA and RNA, also apart of the ADP and ATP molecule which is how energy is released and transported within plant cells. ATP plays a critical role in photosynthesis which is how plants generate sugars to store energy. Generally you will see a higher phosphorous quantity in a fertilizer for fruiting and flowering. Those are very energy intensive actions so the plant needs more phosphorous to ramp up the growth.
- Potassium: not a constituent of any plant structure. The key function of potassium is water movement in and out of the cell. That is important to ensure the correct water balance is in each plant cell.
In addition to Nitrogen, Phosphorus and Potassium, the other plant macronutrients include Carbon, Oxygen, Hydrogen, Calcium, Magnesium, and Sulfur. They are considered macronutrients because they are needed in the greatest quantity by plants. One important thing to remember is that hydrogen, carbon and oxygen are not considered fertilizer. So do not look for those when buying fertilizer. Those three molecules are acquired via water(H2O) and carbon dioxide(CO2).
- Carbon:Carbon is the organic molecule. In fact that is what Organic chemistry is, study of chemistry of carbon containing molecules. These molecules make up roughly 45% of a plant. Carbon is a key molecule for the structure for carbohydrates. Carbon is used in photosynthesis(energy creation).
- Oxygen: Oxygen is also very important to plants for photosynthesis in the form of water and carbon dioxide. The purpose of photosynthesis is to create glucose(sugar) for plant energy. Any unused oxgygen is released via plant leaves which is how aerobic organisms(humans are an example of aerobic organisms!) get the oxygen needed for life.
- Hydrogen:Hydrogen is a major part of the glucose molecule. It is also a major element in many different important biological molecule.
- Magnesium:The main purpose of magnesium in plants is for the chlorophyll molecule. Chlorophyll is one of the most important molecules in plants and responsible for photosynthesis magnesium is obviously needed. Magnesium is also needed for enzymatic activation for the production of DNA, RNA and ATP. All very important for plant life.
- Calcium:Calcium has a ton of functions in plants. It is a part of cell walls, a part of enzymes, and is very important for cellular transportation of other molecules.
- Sulfur: Sulfur is important for methionine and cystine. Both of those are amino acids that impact respiration, metabolism, and photosynthesis. In addition the sulfur offer some protection from predators of the plants by impacting the flavor of the plant.
Plant Micronutrients are those that are not needed in as large of an amount as other nutrients. Having said that it is not to say that these are not important. Plants still need these to grow properly. The list of the important micronutrients are:
- Boron:Boron is needed for cell walls and also for potassium transportation. It is also in the structure of pollen tubes which is extremely important. It also is important for carbohydrate metabolism by regulating sugar and starch concentrations. Boron is also important for the metabolism of other molecules including amino acids. It helps with the use of water and calcium as well.
- Chlorine: Chlorine is needed for the electrical balance in cells. It is the balance to potassium in the cell which is important for osmosis. Chlorine is also used in the breaking of water bonds in photosynthesis.
- Iron: Iron is very important for photosynthesis because it is apart of the creation of chlorophyll although is not a part of the molecule. It is important for electron transfer and in enzymatic functions. Iron is used in nitrogen fixation and is a part of protein.
- Cooper:Cooper is involved in photosynthesis and enzymatic function and has similar functions to iron. It is also important in the production of lignin which is an important part of adding rigidity in cell walls.
- Molybdenum:It is important for creating organic compounds that include phosphorus. It is also important for nitrogen fixation in bacteria.
- Manganese:It is important in the construction of chloroplasts and in photosynthesis. Manganese is used in the bond breaking of water in photosynthesis.
- Zinc: Zinc is used in many enzymes, one extremely important to the creation of called auxin. Auxin is a primary plant growth hormone. Zinc is important for RNA,DNA, and in photosynthesis and carbohydrate metabolism.
- Nickel: Nickel is used for the activation of urease which is needed for nitrogen metabolism. Without Nickel urea builds up and it causes toxicity in plants.
Selecting Fertilizer and Other Nutrients
The nutrients above are key for plant growth. Many of the micronutrients are available as supplements and it is important to note that they probably are in the required quantities in the soil. Fertilizers will generally contain some micronutrients but will focus on the macronutrients. To properly select a fertilizer do research on your plants to understand their nutritional needs. Nutrition obviously varies for numerous reasons one main one is plants that fruit vs ones that do not.
Some plants need other micronutrients that are not on the list above. Some of them include Silicon, Sodium, Vanadium, Selenium, and Colbalt. Again do your homework on what your plants need to ensure they get proper nutrition. I will suggest the wikipedia page on plant nutrients and the book Teaming with Nutrients that I have referenced below for further research past this article.