Plants come in many shapes and sizes and feature many different characteristics that attract gardeners. However, they all get their food, light and water in the same basic ways. Understanding the process will help gardeners better care for any plants they wish to grow.
Plant leaves are specially designed to absorb light and convert it into energy. Chlorophyll is the pigment in leaves that both makes them appear green to us and absorbs the rest of the spectrum of light for energy conversion. This process, called photosynthesis, converts light and carbon dioxide into sugar and oxygen. Oxygen is released into the atmosphere, and the sugar powers the plant's growth.
The root systems of plants are roughly the same size underground as the foliage aboveground. These roots are made to absorb water, the same way that leaves are made to absorb light. Proper soil composition is essential to plants for this reason. Compacted soil makes it difficult for roots to grow and burrow through the earth in search of water. Soil that retains too much moisture can induce root rot and invite soil-borne diseases. Soil that does not retain moisture can inhibit plant growth.
Plants use the energy generated by photosynthesis to absorb water and nutrients through their roots. Water helps the roots absorb nutrients from the soil. Soil that is excessively sandy allows water to wash nutrients out of the soil, making them unavailable for the roots. Soil that is not the right pH level for a plant may have the necessary nutrients in it, but the incorrect pH level may make them inaccessible to a plant's roots.
Plant fertilizer, or food, is beneficial to plants when it is appropriately applied. Fertilizer needs differ by plant, and applying the wrong fertilizer can be detrimental to plants. In addition to applying the correct fertilizer, gardeners must pay strict attention to the manufacturer's recommendations for application amounts and methods.
Too much food, light or water can all be detrimental to a plant's health, as much or more so than too little of any of these things. Gardeners should note each plant's specific needs and cater to them. Unless a garden consists of only one species of plant, there is no one-size-fits-all approach to tending plants in a garden.