Compost tea is a water extraction of compost. The micro-organisms present in the compost is multiplied by adding selective nutritive substrata. As the amount of microbes in the extraction increases, the levels of dissolved oxygen decreases and thus air is constantly bubbled through the system to keep the extraction aerobic. After 48 hours this brewing process is complete and the compost tea then consists of nutritive materials (organic compounds, micro and macro elements) and a wide variety of beneficial bacteria, fungi, protozoa and nematodes. Compost tea’s efficiency depends on the quality of the compost, the system's extraction efficacy and the ability of the added food to increase the organisms without sacrificing the biodiversity.
A nematode that feeds on bacteria (bacteriovore). In the nematode's "gut" small spots of bacteria
can be seen. [400 x magnification]
Most protozoa in compost tea feed on bacteria. Here a cilliate (a genus of protazoa) can be seen.
They have very small hair-like structures (F), called cillia, that move the fluid and bacteria into
its vacuoles where it is digested and nutrients absorbed. Notice the tail-like structure (A) it uses
to anchor itself to a piece of organic matter. The dark piece in the left bottom corner is a small
particle of organic matter. [400 x magnification]
This protozoa, a cilliate, has the same feeding mechanisms as the one in the figure above. Here four
"heads" can be seen on the one tail-like structure. All four are actively feeding on bacteria. The
dark piece is a small particle of organic matter. [400 x magnification]
Here another genus of protozoa, an amoeba (A), can be seen. Small, round protozoa called flagellates
(B and C) are also visible. [400 x magnification]
Ecosoil's compost tea has specific fungal food additives which increase the fungal biomass in the tea.
Here fungal strands called "hyphae" can be seen surrounding pieces of organic material. [400 x magnification]
Why use compost tea?
Natural systems like fynbos are healthy and do not need external input for their nutritional or pest control requirements. Thirty percent of the sugars that the plant manufactures via photosynthesis are secreted by the roots to feed the micro-organisms around its roots. The secretions differ between plant species and select different combinations of microbes. Highly diverse systems such as fynbos therefore have a highly diverse microbe community. These microbes protect the plant against pests and diseases through the coverage of potentially infectious areas, by being more competitive regarding food and the inhibition of pathogenic growth. Certain microbes feed off other microbes, which help to keep pathogenic populations under control. It is estimated that 75% of all insects spend a part of their life cycle underground. A healthy soil with a diverse microbe population and high organic material content help to keep pest populations under the economic threshold value.
Bacteria and fungi have high levels of nitrogen-rich proteins. Nutrients are immobilised when these organisms breed and ingest the nitrogen and convert it into protein in their bodies. Thus leaching of nutrients is prevented. In the spring this captured nitrogen must be made available to the plant again. This is facilitated when bacteria and fungi are consumed by protozoa, nematodes and arthropods.
If the conventional farming approach is adhered to, soil becomes marginal and poor in organic material, necessary nutritional elements and micro-organisms. Plants that otherwise grow well in nature, need constant attention and expensive input when cultivated in monoculture. Root secretions of the crop can only feed a limited variety of microbes and these few favourable organisms are further reduced by the usage of toxic substances and high concentrations of fertilisers. The amount of natural predators decrease to such low levels that pathogens cannot be controlled naturally and therefore pests and disease take over. Further chemical interventions are required, which is an expensive exercise for the farmer and also weakens the system even further. The fact that farmers add 4 to 6 times more nitrogen than the crop requires is a perfect example of this. Ecosoil’s compost tea has the necessary diversity to, as part of a holistic management plan, increase fertility and health of your soil to such an extent that you can save considerably on fertiliser and spray purchases.
(See farmers comments and research section)
