BioLogic Systems has conducted extensive research in order to better understand what specific methods and materials actually produce the exceptional benefits that are touted by compost tea enthusiasts.  Thorough testing of our products and organic materials has revealed many factors that influence the process of making effective compost teas.

The BioLogic Method™ relies on high-quality inoculants including humus, composts, and mycorrhizal products.   In order to stimulate microbial reproduction, “food stocks” such as kelp and fish hydrolysate are added.  The liquid form of these ingredients can be easily applied to plants using root drenches and foliar sprays.  Application quantity and timing vary depending on the crop and climate.

Many philosophies exist in regards to how to make and use compost tea.  BioLogic Systems has adopted the following terms “Compost Extract” and “Active Aerobic Compost Extract (AACE)” to describe the specific processes we recommend.

  More recently, we at BioLogic Systems have adopted the term “Liquid Biological Amendments (LBA)” when describing these types of applications.  Given the variety and lack of consensus over the definition of “Compost Tea”, we believe LBA to be a more accurate title for the concepts mentioned within our informational material.

Liquid Biological Amendments:
Instant LBA vs Brewed Compost Tea

What Are Liquid Biological Amendments?

At BioLogic Systems, we prefer to use the term “Liquid Biological Amendment” (LBA) rather than “compost tea.” We no longer recommend that it is necessary to aerate or brew an LBA for an extended period of time. When working with tested inoculum-grade inputs that contain proven beneficial biology, a very potent “Instant LBA” can be achieved by simply liquefying and applying the products to plants immediately without allowing time for brewing. After conducting numerous side-by-side trials comparing a brewed LBA versus an Instant LBA, we have concluded that the brewing process is not necessary and that the focus should be on using quality input materials. Instant LBA’s can be made for both root drench and foliar applications. Although some specific contexts still exist for aerobically brewing an LBA in large agricultural contexts, we feel the professional hobby gardener or small-scale farmer can achieve maximum results without this added process.

The Instant LBA approach may have many advantages over “brewed compost teas” including:

• Time Savings – Instant LBA’s can be made in a few minutes anytime on the fly.
• Eliminate the need for expensive air pumps, compost tea brewers, and tanks.
• Increase the odds of growing the “correct microorganisms” for your plant by allowing the reproduction of the organisms to occur in the soil and   on plant surfaces rather than in a compost tea brewer. Extended brewing periods will select for organisms that can grow in water, which may or     may not be the correct biology for your specific plant.
• The Instant LBA approach allows the grower to mix a highly concentrated LBA with no risk of it culturing anaerobic pathogenic organisms.
• Reduce anaerobic biofilm accumulation in tanks and hosing that is caused by exposure to highly active LBA’s.

Compost Extract

“Compost Extract” is made by releasing the clinging microorganisms and nutrients from high-quality compost into a container filled with water.  Making compost extract is a very easy and efficient process; a batch of compost extract can be made in about five minutes.  First the compost is placed into a mesh bag.  Then a mechanical or manual motion pushes the microbes and nutrients through the mesh into the water.  Next, microbial foods (fish hydrolysate, kelp, etc.) are added to the water.  Once the extract is applied to the soil, the microbes consume the added foods and reproduce.

Active Aerobic Compost Extract (AACE)

“Active Aerobic Compost Extract” (AACE) is used for foliar applications. Making AACE involves an additional step, often called “brewing,” that requires a “tea brewer.”  The compost extract (described above) is aerated for one hour or more allowing for aerobic microbial reproduction in the brewer.  During the aerating (brewing) period, the microorganisms emerge from their dormant state and reproduce.  As the microbes grow, they produce a slime layer (a “bio-glue”) around themselves that increases their ability to adhere to leaf surfaces when sprayed.  AACE takes 18-72 hours to brew depending on the ambient air temperature.