Water is one of the most important elements to the plant, and the survival and growth rate of a plant is affected by how much water the plant takes in. However, plants do not need an infinite amount of water and instead prefer specific amounts based on the plant species. This water helps the plant perform the majority of its functions.
Plants absorb nutrients in the water, which often came from the soil. This is why the water usually needs to soak into the soil. Cells absorb water by changing the amount of salt and potassium in the cells, which causes water to flow into the cells in order to dilute the concentrations, according to Michigan State University.
Different plants need different amounts of water. Some desert plants, such as cacti, are designed to be able to go for long periods of time without water.
Plants can make almost everything they need out of water and some other nutrients. The energy that the plant lives off of is made by splitting water into hydrogen and oxygen and then the hydrogen and carbon dioxide in the air are used to make sugar, according to Michigan State University. The amount of water that the plant takes up affects how large their flowers are, how long the flowers stay on the plant and how big their fruit is.
Plants have waxy cuticles in order to reduce the amount of water they lose. However, when they have too much water, they release it through openings in a process called transpiration. They close up if they don't have enough water, but this process stops photosynthesis and plant growth. Roots have root hairs in order to maximize the amount of water that is taken up by the roots, according to Michigan State University. The water comes into the roots by the root cells filling themselves with sugars, which causes the water to come in to dilute the sugar.
Plants do not start taking up water until the leaves start to develop. The leaves lack waxy cuticles and lose water quickly. However, the leaves produce more sugar through photosynthesis, which allows the roots to take up water more quickly, according to Michigan State University.
Too much water is worse for a plant than not enough water. Plants that are overwhelmed with water will lose some of their roots, which they cannot replace until the next season, according to the University of Tennessee. Too much water causes a chain reaction. First, the plant cannot absorb enough oxygen and has to switch to anaerobic respiration. Then, the plant releases byproducts such as ethanol. Ethanol interferes with the plant's ability to absorb water and nutrients.