How to feed plants
Plants need a wide range of elements, or nutrients, to survive. While they need different quantities of each one, a deficiency in any one of the nutrients can reduce the plant’s ability to function. Plants obtain most nutrients from the soil and absorb them as they take up water. In the cases of oxygen, carbon and hydrogen, the plant obtains these nutrients from the atmosphere (in the form of carbon dioxide and oxygen) and from water.
Below is a list of the nutrients plants require and what they are needed for:
| Nutrient (element) | Used in…* |
|---|---|
| Macronutrients | |
| Oxygen (O) | Photosynthesis Respiration Chlorophyll |
| Carbon (C) | Photosynthesis Respiration Chlorophyll |
| Hydrogen (H) | Photosynthesis Respiration Chlorophyll |
| Nigtrogen (N) | Chlorophyll Proteins Amino acids Nucleic acid |
| Phosphorous (P) | ATP (the compound which carries energy around the plant) Nucleic acid |
| Potassium (K) | Opening and closing the leaf stomata Activating enzymes |
| Calcium (Ca) | Cell wall structure Enzyme cofactor |
| Magnesium (Mg) | Chlorophyll Activating enzymes |
| Sulphur (S) | Proteins Amino acids |
| Micronutrients | |
| Chlorine (Cl) | Probably essential for photosynthesis Osmosis and ionic balance |
| Iron (Fe) | Chlorophyll |
| Boron (B) | Enables use of calcium within the plant Nucleic acid synthesis |
| Manganese (Mn) | Activating some enzymes Photosynthesis |
| Zinc (Zn) | Enzymes Activating enzymes |
| Copper (Cu) | Enzymes Activating enzymes |
| Nickel (Ni) | Enzymes |
| Molybdenum (Mo) | Enables use of nitrogen within the plant |
* We have included some of the main uses for each of the nutrients, however this is by no means an exhaustive list.
A ‘balanced’ fertiliser contains an equal proportion of nitrogen, phosphorous and potassium, often expressed as NPK 1-1-1. Often balanced fertilisers will also contain other nutrients.
To increase nutrient levels, fertilisers or other sources of nutrients can be used:
