The Professional Tree Care Co.

Tree Care, Pruning, Removal & Maintenance Services for Commercial and Residential Clients.

What is Aerobically brewed Compost Tea?

Compost tea is a liquid produced by leaching soluble nutrients and extracting bacteria, fungi, protozoa and nematodes from good quality tested compost.

Tea production is a brewing process that under proper conditions can be relatively easy. However, for the inexperienced, brewing compost tea can be fraught with problems. You must have the correct compost mixture and tea-making machine which brews tea aerobically.

Compost tea must also be tested at least three times a year to ensure a quality product.  If you buy compost tea from someone who is not getting their tea tested you have no way of knowing whether you are buying beneficial aerobically brewed compost tea or ineffective
brown water.

In order to make Actively Aerated Compost Tea you need to assure your base compost has a highly beneficial group of soil microorganisms such as bacteria and fungi, protozoa and possibly nematodes present. You must make certain it is tested using microscopy, NOT plate counts. Then you apply the tea to the soil as a drench and to the leaves as a foliar application.

Aerobically brewed Compost tea is used for two reasons:

1. To inoculate microbial life into the soil or onto the foliage of plants,
2. and to add soluble nutrients to the foliage or to the soil to feed the organisms and
   the plants/trees present.

The use of aerobically brewed compost tea is suggested any time the organisms in the soil or on the plants are not at optimum levels.

Chemical-based pesticides, fumigants, herbicides and some synthetic fertilizers can kill a range of the beneficial microorganisms that encourage plant growth and compost tea is a proactive way to help restore the life in the soil and on plant surfaces. High quality aerobically brewed compost tea will inoculate the leaf surface and soil with beneficial microorganisms, instead of destroying them.

Benefits of using compost tea containing the entire group of beneficial soil organisms include:

• Improve plant growth by protecting plant surfaces with beneficial organisms that occupy infection sites and prevent entry by disease-causing organisms.
• Improve plant growth through nutrient retention in the soil and reduction of fertilizer requirements.
• Improve plant nutrition by increasing nutrient availability to the root system with predator-prey interactions and increase plant available nutrients in exactly the right place, time and amounts that the plant needs.
• Reduce the negative impacts of chemical-based pesticides, herbicides and fertilizers on beneficial microorganisms in the ecosystem.
• Improve uptake of nutrients by increasing foliar uptake as beneficial microorganisms increase the length of time that the leaf stomates stay open, while at the same time reducing evaporative moisture loss from the leaf surface.
• Reduce soil compaction by building better soil structure. The biology in compost tea builds soil structure, and ALL the groups of beneficial soil organisms we brew are required to be successful. Bacteria alone cannot do the whole job, you must have fungi, protozoa, nematodes and microarthropods as well! Be aware that plate count methods don't tell you about the whole group of beneficial soil organisms.

When is it good to apply compost tea?

• The typical answer in biological systems, is it depends on how healthy your trees and plants are.  Many factors such as recent transplantation or construction damage can apply and a site inspection is suggested.
• If the trees and plants are perfectly healthy the rule of thumb is one foliar treatment per year due to air pollution and one soil application in the very beginning of spring per should be sufficient. 
• If the plants are stressed they will need anywhere from 1-3 applications in the fall and 2-5 applications in the spring over a two to ten year period.