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When a houseplant has not been repotted or fertilized for many years, signs of distress may appear, such as yellowing leaves.
Like all living things, plants need specific nutrients to reproduce, carry out photosynthesis, and maintain homeostasis. Which nutrients do plants need to thrive?
Healthy plants need organic, carbon-based compounds that form plant tissues, as well as inorganic nutrients, commonly called minerals, that support growth and metabolism.
About 17 nutrients support all of a plant’s biochemical needs. These elements are called essential nutrients. No other elements can replace them, and without them, a plant cannot complete its life cycle.
Among the essential nutrients are carbon, hydrogen, and oxygen, which come from the atmosphere and water. Most plants get all other essential nutrients from the soil where they grow.
The two groups of essential nutrients are macronutrients and micronutrients. Macronutrients include carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur. Plants need these elements in relatively large amounts.
Carbon makes up about 45 percent of a plant’s dry mass and is a key part of proteins, nucleic acids, and carbohydrates.
Nitrogen is also a key part of nucleic acids, proteins, and the photosynthetic pigment chlorophyll.
Potassium helps control gas exchange by regulating stomatal opening and closing, which affects water balance.
Essential plant nutrients needed in smaller amounts are called micronutrients. These include chlorine, iron, manganese, boron, zinc, copper, nickel, and molybdenum, which are needed for proper plant function.
Some micronutrients act as cofactors, which help enzymes work properly. For example, iron acts as a cofactor for enzymes in mitochondria.
If a plant lacks an essential nutrient, it begins to show symptoms like chlorosis, or yellowing of leaves. The specific nutrient deficiency can often be identified by examining the plant’s appearance and the soil nutrient content.
Balanced soil nutrient levels help maintain plant health because both deficiencies and excesses can affect growth, metabolism, and overall development.
Even though many essential mineral nutrients are needed in relatively small amounts, all essential nutrients are necessary for plant growth and homeostasis.
Like all living organisms, plants require organic and inorganic nutrients to survive, reproduce, grow and maintain homeostasis. To identify nutrients…
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