The two main types of green fertilizer are manure and compost. Another way to fertilize gardens naturally is by plowing dead plant growth back into the soil. Many gardeners prefer using green fertilizer because it decreases the likelihood of unwanted chemicals entering the food supply.
Cow manure is probably the most common type of green fertilizer. Gardeners like it because it does not burn plants, and it contains many of the chemical properties necessary for healthy plant growth. Cow manure is made up of nitrogen, potash, and phosphate and many undigested bits of organic material, all of which make excellent fertilizers.
Fresh cow manure can be immediately spread on garden beds; however, dried manure must first be crushed or crumbled. Dried manure should then be raked over a freshly turned bed, making sure that distribution is evenly spread. When using either fresh or dry manure, in most cases, following spreading, it is a good idea to lightly water the area.
Other types of manure that are often used as green fertilizer include chicken and horse manure. Both these types of manure offer many of the same nutrients as cow manure. If the manure has to be purchased, horse manure is usually a bit more expensive than cow manure, while chicken droppings are usually less expensive. One drawback to using chicken manure is that it is considered the most odorous of all the manures. Not only is the smell excessively strong, but it can linger in the air for many days.
If keeping the garden completely organic is an issue, it is necessary to make sure that the manure fertilizer comes from animals that are free of hormones and medicines. It is possible for trace elements from medications and hormones to make their way into animal waste. One way to be sure that does not occur is to first add the manure to a compost heap. The bacterial effects of the heap will help eliminate any non-organic content in the manure.
Compost heaps are piles or organic matter that are allowed to ferment over time. Any type of organic matter can be added to a compost heap. Most people begin their compost heaps using table scraps and peelings from fruits and vegetables. In most cases, it takes about six months for a compost heap to ferment enough to make a good green fertilizer. Once the compost is ready, it is simply turned into the garden bed, and then lightly watered.
Another method of fertilizing organically is to allow old plant beds to die out, and then plow the dead remnants back into the soil. This dead plant life will eventually release nutrients into the soil that will enhance new plant growth. Farmers have been using this method of fertilizing for centuries.