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Aerated Compost Tea

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Aerated Compost Tea

The Key to Organic Growing

Compost Tea Brewer with Aeration UnitOne of the most important components of a green program for your garden is aerated compost tea. This tea when produced properly will reintroduce necessary biology back into your garden. With repeated applications your soil will be alive again. Your garden will require less water and almost no fertilizer. Your plants will thrive and your blooms will have stronger color. This is my fourth year using compost tea and my garden and lawn have never been better. As an avid exhibitor I needed to be convinced my show blooms would stand up to all comers. I think this was proven this past show season. In exhibiting at 6 shows 60 of my entries made it to the Court of Honor including Best Basket in Show at the 2008 ADS National show and Best AA/A at the Long Island Dahlia Society show. Equally as important my display dahlia garden in the front of the house has been in bloom all season and today (October 15) it still is loaded with blooms. Pest seem to avoid my garden and I know I used less water in the dry periods. I am ready to attribute much of this success to the use of aerated compost tea. So lets take a look at “What is Aerated Compost Tea?”

Aerated Compost Tea (AACT or ACT) - This process involves adding oxygen to the tea and a food source for the biology in the compost. By creating optimal conditions for aerobic microbes, AACT allows you to multiply the biology in the starting compost by over 10,000 times. Many plant pathogens are anaerobic and prefer low to no oxygen conditions. By making sure the tea and the compost itself are well oxygenated and highly aerobic, you can potentially eliminate 75 percent of the potential plant-disease-causing bacteria and plant-toxic products.

For the past 5 years, AACT has become the standard within the organic industry in regards to compost teas. It's currently being used by golf courses, vineyards, farmers, and home gardens with great success.

Compost Tea Basics

Compost tea is an aerobically brewed (not thermally brewed) liquid concentrate of soluble nutrients, organic compounds and elevated levels of microorganisms.

Recipe for tea is basically

  • De-chlorinated water
  • High quality biologically active and diverse compost
  • A food source for the microorganisms to feed on and reproduce.
  • Brew time is 12 hours with the KIS brewer

Compost Tea Brewer ComponentsBacteria and fungi grow in a brewer at exponential rates because the water contains high levels of oxygen (it's aerated) and a food source (kelp, molasses, humates or hydrolyzed fish) has been provided.

Some species of bacteria reproduce every twenty minutes- start with 10,000 of a species at brew time, 12 hours later you may have tens of millions of this one species.

Compost Tea replicates only those organisms present in the compost at brewing time. It cannot create beneficial fungi if none are present in the compost.

Compost Tea has a rather short shelf life after brewing is complete (4-6 hours) because without aeration the bacteria begin to use up available oxygen and the tea goes anaerobic. Shelf life can be extended with additional aeration. Without aeration most beneficial bacteria quickly die and harmful anaerobes can begin to grow.

Compost Tea can be applied to foliage or as a soil drench. It can be used on all ornamentals, vegetables, herbs, small fruits, turf, annuals and perennials. Different teas can be brewed for different plant groups or plant needs. Most vegetables and annuals require a bacterial dominant tea, turf would require an equal ratio tea, while most woody ornamentals would need a fungal dominant brew.

The different tea brews are determined by the makeup of the compost and the food source added to the water at brew time.

Bacteria, fungi, nematodes and protozoa are responsible for nutrient cycling in the soil. They are the ones releasing nutrients to plants. At high enough populations, less fertilizer is needed. It could even be eliminated under ideal conditions.

Properly brewed tea can be applied to foliage to suppress disease. Powdery mildew, black spot and rust can all be controlled or eliminated by regular foliar applications of Compost Tea. There is less room left on the leaf surface for disease organisms when at least 70% of the leaf surface is occupied by beneficial bacteria and fungi.

Organisms that cause turf diseases can be suppressed by regular applications of Compost Tea. Disease causing fungi cannot compete with high populations of beneficial organisms.

Compost Tea is applied at 5 gallons to an acre. Almost impossible to apply too much, too often. As long as food sources (Hydrolized Fish Fertilizer is an excellent food) are available in the soil, a single application of tea gives enormous benefit for months or years to come. Establishing a true sustainable soil system.

After brewing the compost for 12 hours for the 5-gallon KIS sprayer on your plants or lawn. The backpack sprayer has a more useable nozzle that will not clog with the application. You may also apply with a watering can directly to the roots Application should be done in the morning or under cool conditions. It may be done in the rain when applied to the soil. When applied to leaves, it should be done during dry conditions and be allowed to dry for at least 20 minutes. 

The compost tea is most effective when used within 4 hours after the brewing process is completed. When the machine is turned off their population starts decreasing and you will want to use the tea when it has the highest microbe count. Four hours is the maximum time delay before application.

Frequency of Application

The frequency of application is dependent upon your region, the particular plant and its susceptibility for disease, weather conditions and other factors may apply.  You cannot over apply. I myself make 3 applications each year.

Early spring, before planting out a soil drench.

  • Mid summer as plants leaf out a foliar spray to protect the dahlia foliage.
  • Late fall. After I spread my ground up leaf cover to the beds. This late fall application along with my worms will assure most of the leaves will be consumed and the nutrients will get into the soil by spring.

I use and recommend the KIS 5 gal brewer. Note: The KIS 5 gal brewer is my 3rd brewer. I made the mistake of not reviewing test results of the 2 previous brewers I bought. Both cost more that the KIS. Whatever brewer you buy be sure the company has available test results by Soil Food Web.

Compost Tea Brewer

$139.00

5 gallon brewer includes compost and food for three brews.

Note: 5 gallon bucket is not included. Purchase or obtain locally at a home improvement store.

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