Fertilizer - Any of a large number of materials spread on or worked into the soil to increase its capacity to support plant growth.
Your choice of fertilizers is one of the most important decisions that you may make in your life. But, have you ever read a consumer report or university study on fertilizers? Chemical fertilizers produce weaker plants that are less nutritious to us and necessitate the use of pesticides -- thereby exposing yourself, your family and your pets to these dangerous products.
Countless studies continue to document the problems that decades of improper fertilization are causing. We spend millions of dollars on fertilizers every year but we make very uneducated decisions on them. In fact, most of our decisions on fertilizers are based on advertising alone.
Many different types are available today: chemical, organic, natural, liquid, dry, slow release and water soluble. We have different ones for our lawn, flower garden, trees and shrubs, houseplants, and our vegetables ... but what do you really need?
For many years we thought that plants simply lived off of nitrogen, phosphorus and potassium (NPK). Later we found they also needed trace minerals like iron, calcium and magnesium to keep them healthy.
Today, we are discovering that soil fertility and resulting plant health is not limited to the mineral content of the soil or fertilizer. The area that surrounds the plant roots is called the rhizosphere and it is home to millions of interacting microorganisms called soil microbes that play a key role in plant health.
Soil microbes require many of the same nutrient elements that plants do, and they will compete with plants for these nutrients. Some of these microbes actually feed off nutrients produced by plants. In fact, some studies have found that as much as 20% of the chemicals that plants produce by photosynthesis may be released from the roots into biologically active soil. Much less is released into sterile soil.
However, these soil microbes repay plants for what they take. They are prolific producers of vitamins, amino acids, hormones and other growth regulating substances. Soil microbes affect plant welfare in a number of other ways, many of which are not yet fully understood. We do know that these organisms make nutrients in the soil available to plants, stimulate plant growth and inhibit the growth of or kill disease organisms and plant pests.
Some of these benefits are the result of simple interactions between roots and microorganisms and some are the result of complex activity between several different organisms. The more we can complete the plants total requirements, the better they grow.
Nitrogen fixation
Air is 80% nitrogen yet lack of nitrogen is usually the limiting factor in plant growth. Certain microbes have the ability to absorb nitrogen from the air and provide it to their plant hosts. In return the plant provides nourishment for the microbes. Despite all the money spent on chemical fertilizer, nitrogen-fixing microorganisms account for 70% of our total agricultural requirements with the remainder being chemically produced and added.
Mycorrihizal Fungi
Most plants, whether wild or cultivated, have roots that are infected with fungi that increase water uptake and protect plant roots from certain diseases. These roots are called mycorrhizae and the fungi that infect them are known as mycorrhizal fungi. This condition is normal for most plants and if it is not present can greatly affect plant growth. These fungi obtain their food from plant roots and are unable to exist without this plant created nourishment although they can exist in the soil for years as spores.
Microbial control of soil pests
Many soil organisms that cause plant problems are often suppressed by soil microbes. Just as in the human body, disease-causing organisms may be present, but little or no harm is done because of natural biological controls that limit their populations. Cultivation techniques such as crop rotation reduce pathogen population by starving them since it removes their host food source.
It is also possible to increase the level of beneficial organisms that control soil problems. This usually cannot be done by simply adding these organisms but is best accomplished by using organic amendments that provide a better environment and food source for beneficial microbes. One example of this was studies that were done using nematode trapping fungi. These fungi trap and kill nematodes using sticky nodules. However, introduction of these fungi into the soil failed to increase nematode control, probably because the soil did not contain the proper environment to support a fungi population sufficient tocontrol the nematodes. Likewise, poor soil condition caused by chemical fertilizer use is largely responsible for the drastic decline of our earthworm population. Simply adding worms to our soil won’t help unless we change fertilizer methods and create healthier soil. These examples support the ecological principle that says population is a reflection of the habitat.
Looking Forward
Today, we are able to look beyond using chemical fertilizers, or organic fertilizers that provide only a limited range of mineral nutrients -- to a new generation of fertilizers that are capable of making plants truly healthy. Proper fertilization will decrease our dependence on substances like pesticides which have proven to be a major environmental problem.
Another major benefit for us will be the production of food that is once again rich in all the essential nutrients and chemicals plants produce that keep us healthy and protect us from many illnesses – like the food of previous generations. Healthy plants grown in rich soil produce the most nutritious food.
To grow healthy plants, look for fertilizers that are rich in trace minerals, biologically active (containing beneficial fungi, bacteria and more) and contain organic substances that encourage microbial activity. And, look for plants that are grown this way. They will not suffer from transplant shock --which is proving to be the period it takes for these microbes to get established in the root zone -- and they will be healthier and more maintenance free for you.
The Hidden Costs of Chemical Fertilizers
The costs of chemical fertilization methods are proving to be astronomical. They are hidden in poor food quality, health care for ourselves and our pets, pollution cleanup, diet supplements, water purification, desertification and countless other expenses. We will be paying these costs for generations to come. Now is the time to begin a green approach to fertilizing ...to help keep the problem from escalating.
