Compost tea is the result of adding high quality compost that is rich in beneficial micro-organisms to water with the presence of oxygen and allow it to “brew”. When these microbes are provided with water, oxygen and a food source the start to multiply rapidly, populating the “tea” with billions of beneficial microbes.
Microbiology from aerobic compost provides numerous benefits to plants and soil. Beneficial micro-organisms compete for resources with the disease causing bacteria (pathogens) resulting in less disease pressure and healthier plants.
The microbes also go to work converting the nutrients from the compost to water-soluble, plant available form. This process makes the organic nutrients more readily available and easier for plants to take up. Soluble nutrients result in a faster response from the plant. Some composts are very rich in nutrients resulting in a tea that works as a fertilizer as well as a soil enhancer. Other composts have very little nutrients and do not provide enough plant food for alone.
Making high quality compost tea can be difficult as composts tend vary significantly in quality. Poorly made compost may contain minimal beneficial micro-organisms and could potentially carry harmful pathogens that could multiply when the compost tea is brewed. Low numbers of microbial populations or the presence of harmful pathogens are often the result of “compost” that was made without oxygen present (anaerobic) or did not have the proper ratio of carbon to nitrogen (C:N) to reach temperature sufficient to kill harmful pathogens.