I ran across an amazing resource I forgot I had. It is the Wisconsin Garden Guide by Jerry Minnich. It is a basic book an all things garden in Wisconsin. I highly recommend this book for gardeners, of all levels. This thought leads to my topic. He has a whole chapter on fertilizing plants. I thought I would share what I understand about plant nutrition.
Fertilizers come in basically two forms, chemical or organic. This leads to the great debate about which to use. I have been known to use both successfully, though I lean towards the organic for reasons I shall briefly discuss.
The commercial fertilizer industry began in Germany in 1861. Chemical fertilizers are produced by combining substances which provide the essential nutrients needed for effective plant feeding. Basic fertilizers contain nitrogen, phosphorus, and potassium. Ammonia, a source of nitrogen, is synthesized by using natural gas and air. Phosphorus is made using sulfur, coal, and phosphate rock. Potassium comes from potassium chloride, found in potash. These fertilizers are taken up immediately by the plant, essentially giving the plant a quick boost. Production of chemical fertilizers requires a fair amount of mined resources to produce, ie. natural gas, coal, sulfur, phosphate rock.
Organic methods of fertilizing have been around for thousands of years. Plant nutrition has been supplemented by the addition of compost, animal manure, green manure, or other forms of natural fertilizer (a form of recycling). Organic fertilization is a continuous process of feeding the soil rather than focusing on simply feeding the plant. The addition of organic material builds and supports whole ecosystem of life hidden just below the surface of the soil. This ecosystem becomes fully capable of supporting healthy plant growth.
So, the debate shall forge on, chemical or organic. The debate becomes a philosophical difference between feeding the plant and feeding the soil. I shall leave that decision up to you. Perhaps one approach is a combination of both.
Back to the nutritional needs of plants and a breakdown of the various components of fertilizer. Plants have three major nutritional needs; nitrogen (N), phosphorous (P), and potassium (K). The numbers on fertilizers represent the percentage of each of these three elements. For example, Miracle-Gro may have the numbers 24-8-16. This means that there is 24% nitrogen, 8% phophorous, and 16% potassium. Nitrogen helps plant grow strong and healthy above the ground while keeping the leaves a nice dark green. Yellow leaves along with stunted growth may indicate a nitrogen deficiency. Phosphorous is responsible for for healthy root growth, bright flower color, and overall plant health. Low phosphorous levels may stunt plant growth and the leaves will have a purplish tinge. Potassium helps plants grow strong stems, reduces water needs, and helps the plant resist disease. Potassium deficiencies are indicated by browning leaves, stunted growth, and small fruit.
Plants have other nutritional needs that are often not available through chemical fertilizers. These are micronutrients and trace elements. Calcium helps neutralize toxic wastes that might develop and helps keep the soil at a proper pH range. Other elements such as iron, magnesium, boron, cobalt, copper, molybdenum, manganese, and zinc play an important role in plant health, though are needed in very small quantities. A good organic feeding program will help your soil supply these elements to your plants. In addition, these same elements are important to human health. They are supplied by the very foods we eat. Hence, another reason to support organic fertilizing methods.
If you would like to read more on plant fertilization, follow this link: http://bit.ly/hPV1XB