Plants clean our air, provide us with food, provide habitat for animals and make our environment more pleasing to the eye. Although needs may vary with different types of plants, there are six basic things that all plants need in order to grow and thrive: air, water, nutrients, light, space and warmth
During photosynthesis, plants take carbon dioxide from the air and use it to produce food for their growth. What is left over after photosynthesis is oxygen, which they put back into the air for us to breathe. Dirty air blocks sunlight, which is also necessary for plants to grow, and may prevent plants from absorbing enough carbon dioxide.
Sunlight is used by plants to convert carbon dioxide and water into sugars through photosynthesis. In the absence of sunlight, plants cannot produce the food that they need to thrive. Plants that do not get enough sunlight will have thin, spindly stems that lean toward the light and may wither and die if more light is not received. Plants that receive too much sunlight will grow poorly, as well, becoming bleached or blistered. A plant that requires full sun needs eight to 12 hours of unfiltered sunlight per day, and one that requires partial sun needs from five to six hours. Plants requiring partial shade need indirect or filtered light, and should only receive direct sunlight for short periods of time each day.
Like all living things, plants need water to survive. Water is the conduit for nutrients and food that plants need. The amount of water needed will vary for different types of plants, because some, such as African violets, prefer moist conditions and others, such as cactus and succulents, prefer drier conditions. As a general rule, if the soil feels dry to the touch, plants should be watered.
There are three main nutrients that plants get from soil: nitrogen, phosphorous and potassium. In addition, there are secondary nutrients and micronutrients that are also obtained from the soil plants grow in. The amount of each nutrient required varies with different types of plants, and too much or too little of certain nutrients can stunt growth, produce weak plants or even cause them to die. As plants use the nutrients in the soil, they must be replenished with soil additions or fertilizers, or the nutrient content will eventually be diminished.
The amount of space available has a direct bearing on plant growth. Plants with a large area to grow in will extend their roots and thrive. Plants that are crowded or have only a small space in which to grow will have tight, crowded roots, resulting in stunted growth.
In cold climates, few plants can survive, so there is little greenery to be found. Some plants, such as geraniums, require temperatures to be at least 80 degrees F in order to thrive and grow. Other plants can withstand colder temperatures, but very few can survive temperatures that are below freezing. Temperatures should usually be close to that of a plant's native habit to promote the best growing conditions.