Compost Tea Understanding

COMPOST TEA illustrates many preparations created using compost as an initiating material and making a liquid juice or occasionally a “liquid form” of the original compost.

There are many home-designed examples of equipment and some commercially applicable equipment made to make compost tea. Different ideas flourish on how to concoct the better tea-producer, and exclusive designs are tested each year with attempts to improve productivity and cut down costs.

There are possibly as many recipes for compost tea as there are for chili in Texas, with more theories on enhancements and a focus on its use for more unique applications.

For example, when preparing compost tea to fight plant diseases, the tendency is to have as high microbial diversity as feasible.

When creating a tea to supplement plant nutrients, many makers strengthen the tea with supplements either during production or as a postproduction addition.

Optimism about compost tea is huge, but it is necessary to understand its limitations and have realistic expectations. With all the variations in compost tea production, there are some applicable basic guidelines independent of recipe or machinery characteristics.

Quality – From Maturity To Microorganism Competition

Compost tea is a freely accessible form of compost that will influence the plant more rapidly than compost incorporated into the soil.

Compost quality issues, consisting of maturity and microorganism content, are very significant for producing efficient compost tea. The conversion of compost into compost tea cannot advance on the original quality of the compost.

Good compost has the potential to create a good compost tea if performed accurately; a low compost will consistently make a poor compost tea.

Many deficiencies in the initiating compost, such as high salt accumulations, high grades of anaerobic microorganisms, and pathogens, may actually be intensified in the final compost tea.

It is crucial to use only the highest quality compost available. Preserve the lesser quality compost for soil treatments and employ entirely the best for compost tea production.

Microbial Numbers And Diversity

Compost that is plentiful in microbial numbers and diversification can cause compost tea with these same qualities. The common portrayal of microorganisms in compost tea diverges from authentic compost.

Some microorganisms, like to live connected to gritty matter and a compost tea created using a fine-mesh strainer beloved for tea intended for drip irrigation, don’t let an ample amount of particulate matter through to bolster these microorganisms.

The valuable fungi and actinomycetes distinguished in a good compost may be insufficiently expressed in the compost tea simply because of the necessity of straining out the substance to which they would attach because of the needs of the irrigation scheme equipment.

Remember that compost tea microbiology is most influenced by oxygen availability, nutrient availability, and the original microbiology of the compost used to produce the tea.
Compost tea is evaluated for the same microbiological specifications as compost.

This consists of valuable microorganisms incorporating aerobic and anaerobic bacteria, fungi, actinomycetes, pseudomonads, and nitrogen-fixing bacteria, as well as pathogens such as E. coli and Salmonella.

 

 

Remember that compost tea microbiology is highly affected by oxygen availability, nutrient availability, and the original microbiology of the compost used to produce the tea.

Storage And Application Methods

Unlike wine, compost tea seldom advances with time. For outstanding results, it should be used as quickly as possible and should be kept in a darkened area with agitation and ventilation to the reservoir.

Long cache times will adversely influence the diversity of microorganisms and the nutrients transported by the tea for plant use.

Compost teas are employed either to the soil or to the plant vegetation. Those applied to the soil will go into the root zone and influence the plant’s rhizosphere.

Nutrients carried in the tea will be handled by the plant and the microorganisms in the soil. The microbes in the compost tea may face competition with other soil microorganisms but turn into a part of the soil and rhizosphere microbial ecology.

Alternatively, compost teas administered to the plant foliage will instantly influence the plant, and there is very slight room for forgiveness from the plant if tea with harmful traits is used.

Good quality compost will contribute beneficial microorganisms and nutrients to the plant’s surface to benefit the plant in illness suppression and nutrient availability.

A poor quality compost tea may yield the plant surface with undesirable components such as salts and problem microorganisms.

Compost tea destined for foliar applications, in particular, should only be made with the serious quality of compost to avert complications such as salt burn and the delivery of pathogens in critical sectors of the plant.

Compost tea, like compost itself, has the potential to be a powerful tool for agriculture.

Besides being a stand-alone product, growers discover its potential to be a potent carrier for alternative agricultural segments.

Our perception of the science behind this complex product advances to grow and supports us to recognize some of its opportunities and limitations.

Research Trials With Compost Teas

ASED in Santa Cruz, California, the Organic Farming Research Foundation (OFRF) has supported several studies conducted at various colleges on the effectiveness of compost extracts. Jane Sooby, OFRF director, supplied reports of the research to BioCycle, two of which are summarized below:

Sylvia Welke of Olds College in Alberta, British Columbia (BC) used a $3,945 grant to conduct research in 1999 on the effectiveness of compost extracts as disease suppressants in fresh market crops.

Hermann and Louis Bruns of Wild Flight Farm in Mara, BC, and the North Okanagan Organic Association in Vernon, BC were coinvestigators.

Cattle and chicken manure composts were used for the extractions. Both composts were actively turned in the first month and once/month for the next three, then cured for six months.

For tea production, water was added to the composts at an 8:1 ratio, and the mixture was stirred for about ten minutes each day for a week.

The extract was filtered through several cheesecloths and stored out of sunlight. Compost tea was applied with a backpack sprayer at a rate that ensured all foliage was covered.

Crops were sprayed in the field and/or in the greenhouse stage. Each treatment was repeated four times.

Results indicated that cattle manure compost and its extract had fecal coliform counts within acceptable limits and these were not detected in the crops tested.

The Report states:

The effects of compost extract application were not consistent across all crops. Yet, some trends did emerge.

Extracts from cattle manure compost were effective in increasing the marketable number and weights of strawberries.

The same extract also increased the weight of broccoli heads. Lettuce and leaks did not show any increased harvest weights or reduced disease incidence as a result of cattle compost extract application.

Crops that received applications of chicken compost extracts had lower average harvest weights after diseased parts were removed, except for lettuce.

It is possible that the chicken compost extract had some microorganisms associated with it or metabolites that may have further contributed to disease progression or had some other negative effect on plant growth…

This study also gives support to the idea that different crops respond differently to extracts from a variety of sources.

The second season of testing is needed for conclusive results, as weather conditions, the freshness of the tea when applied and other factors may have affected the outcomes.

Richard Merrill and coinvestigators Kay Hoberecht and John McKeon all of Cabrillo Community College in Aptos, California – used a $4,860 grant to study the design of a simple, experimental organic tea extractor and a preliminary experimental protocol.

Using 55-gallon plastic barrels, researchers designed four aerobic tea apparatuses and four anaerobic ones to be used alongside them. Each was filled with 50 gallons of water.

Five gallons of compost produced from food residuals and yard trimmings were added to each in shade cloth bags for the anaerobic barrels and in the feedstock container for the aerobic ones.

After 24 hours, 32 oz of sulfured molasses and 32 oz of azomite rock powder were added to the aerobic barrels, and the anaerobic barrels were mixed vigorously for one minute every four hours up to the 48-hour mark.

Testing indicated minor differences in the bioplate count between the subsamples of compost taken from the same batch. There was no significant difference in oxygen between active (vigorously mixed) and passive treatments over a 24-hour period.

“Our experiments confirm those of others that so-called anaerobic tea systems, those in which organic stock is simply soaked in water, are actually aerobic for the first 48 hours or so of soaking,” states the report.

“In other words, `aerobic’ systems are merely extending the time of useful extraction by putting more oxygen into the system.”

There was little difference in bioplate counts between passive and active treatments during the first 24 hours, but a significant one during the first 48 hours in aerated systems.

The recommendations of the preliminary experimental protocol included:

Use a consistent source of feedstock and take subsamples from the same batch;

Conduct inorganic and bioassay tests on pilot subsamples to establish the degree of feedstock variation; Employ extractors and aeration units of similar design in replications;

Control for the temperature of extraction, the chemical quality of water used, use of supplemental ingredients, and amount of ambient light; and Focus on a minimum number of variables

Sources:

• Organic Farming Research Foundation (OFRF) 
• Olds College in Alberta, British Columbia (BC)
• North Okanagan Organic Association in Vernon, BC