Understanding Compost Tea

Compost Tea and noticing healthier plants and soil, this isn’t just by chance, it is well

known that Compost Tea will help to create a balanced soil food web.

A balanced Soil Food web will:

1. Suppress disease‐causing and pest organisms

2. Improve the nutritional quality of the plant.

3. Produce good soil structure, improving water infiltration, oxygen diffusion, and water

holding capacity.

4. Retain nitrogen and other nutrients such as calcium, iron, potassium, phosphorus, etc.

5. Make nutrients available for plant growth at the times plants require at the rates

plants require.

6. Decompose plant residues rapidly

7. Reduce worker exposure to potentially harmful chemicals

8. Produce hormones that help plants grow.

Understanding Tea:

Before you start brewing let’s take a moment to understand Compost Tea.

Essentially, brewing Compost Tea is a brewing process that extracts microorganisms

from compost followed by microbial growth and multiplication. This includes beneficial

bacteria, fungi, protozoa, and nematodes.

Compost teas contain both a massive total number and a vast mixture of beneficial

microorganisms which perform different functions.

Compost teas are applied either to the soil or to the plant foliage.

When compost teas are sprayed onto the leaf surface, the beneficial organisms suppress

the pathogens by consuming leaf exudates that pathogens would survive on. Pathogens

that land on the leaf surface simply cannot compete with the beneficial organisms and

therefore have a greatly reduced chance to initiate disease in the first place.

Nutrients carried in the tea will be used by the plant as well as the microorganisms in

the soil.

Tea applied to the soil will move into the root zone and affect the rhizosphere of the

plant. The microbes in the compost tea digest organic matter and pass a steady stream of

mineral nutrients to the plant roots. Healthy soils, containing high numbers of diverse

microbes have the capability of passing a full spectrum of mineral nutrients, hormones,

amino acids and vitamins to plants. By enhancing soil biology, compost tea builds the

capacity of the soil to pass nutrients to the plants.

The Brew:

A basic tea recipe would consist of water, a sugar like Molasses and various food

sources such as, Kelp, Humic Acid, Fish, Alfalfa Pellets and an air pump or aerator.

You can adjust your recipes to put an emphasis on bacteria growth or fungi growth.

If we want to feed bacteria we emphasize sugars, a protein source, and provide extra

minerals.

If we want to create an environment suitable for fungi we add more complex foods

which include fish emulsion, soluble kelp, and protein meals. I recommend brewing for

both beneficial bacteria and fungi.

I add the liquids directly into the brewer, and the solids, like the worm castings, we put

in cheese cloth or paint strainer bags. I try to fill my barrel with water and leave it to

heat up and allow the chlorine to dissipate before brewing. Depending on the air and

water temps, the brew could take anywhere from 24 to 48 or more hrs. The big question

is usually “how do you know it’s done”? At first it will be tricky; a good indication is

after you see the foam form on top you know the microbes are alive and growing, you

will see what has been described as “bio‐slime” on the inside of the brewer, as well as on

the strainer bags, this is usually when I stop my brew and apply to my whole patch via

my overheads in order for the entire patch to get covered, as long as it’s brewed at least

24‐48 hrs. The foam it will drop off a bit, as you brew, but remember, as the microbial

numbers increase, the dissolved oxygen levels decrease. It is crucial that air is

continually bubbled through the system to keep the extract aerobic, if you lose power, or

maybe someone trips over the air hose knocking it out, the brew should not be

kept….REMEMBER…when in doubt, throw it out! The Tea should have a sweet smell to

it.

If I notice that the plants need Kelp or Fish, I’ll add it to the brew instead of applying a

separate nutrient application. Another question is usually: “How much tea do you give

to your plants”? The simple answer is: You cannot give your plants too much, when we

brew Compost Tea, we are not brewing a batch of fertilizer, you are applying water with

a ton of beneficial organisms, I’ve applied 100 or more gallons to my patch per week and

have had very happy plants.

The only true way to see if you have a good brew is to put it under a microscope and see

the organisms swimming. I have had my brew tested for Dissolved oxygen, it came

through with flying colors, part of the reason I am a big fan of the brewer I am using,

I’ve used the Soil Soup brewer and other homemade brewers, the current brew and

brewer have produced the best response from my plants, and my soil is filled with

earthworms every season!