How to Make Actively Aerated Compost Tea

Maximize your compost pile by turning it into tea

Actively aerated compost tea refers to a method of multiplying the beneficial microorganisms found in compost by using an aerated water medium. The oxygen pulsing through the tea during the brewing process promotes microorganism population growth. Additionally, having these bacteria available in liquid form makes distribution to your garden simple. These microorganisms thrive naturally in a healthy compost pile and are essential to creating organically functioning nutrient rich soil. In addition to improving the health of your soil, this tea is also an effective fungicide for plants and trees when applied directly to the plant. There are many benefits to using AACT in your garden, benefits more sustainable than the use of standard fertilizers to amend your soil.

Things You'll Need

• 5 gallon food grade bucket with lid
• Compost
• Air stone
• Aquarium water pump
• Cheese cloth or stockings
• Molasses
• Water
• 2 feet of 1/4 inch tubing (possibly)
• Drill

Instructions

1. Use a 5-gallon bucket as the brewer for the tea. Drill four or five holes in the bucket lid, at least 1/4 inch wide. These will serve both as holes for air to escape and to fit tubing from the air pump to the air stone. Connect tubing to the air stone, and then guide the tubing through one of the holes and attach it to the air pump. It may not be necessary to buy tubing, as many air stones and aquarium pumps come with tubing already.

2. Fill the bucket with 4 gallons of water. If using tap water, turn on the air pump and allow the water to bubble for at least an hour to remove chlorine.

3. Add 3 tbsp. molasses to the water and allow to bubble briefly in order to mix with the water. Molasses acts as food for the microbes already in the compost and encourages them to multiply faster as the tea brews.

4. Take one cup of fully developed healthy compost or worm castings and place them in your cheesecloth or stocking. Tie up the cheesecloth to prevent large particles of compost escaping. Place the compost into the bucket, if possible, just below the water's surface.

5. Place the lid on the bucket; turn on the aquarium pump and let the compost brew for at least 12 hours. After 12 hours, the tea will be ready; but make it stronger if you decide to wait longer. If so, remove the compost bag and continue aeration for another 12 hours.

6. Apply to garden soil and plant foliage as desired Do not dilute the tea before use. The tea will be most effective within four hours after brewing. Most microbes will have died from lack of oxygen in the mixture after 10 hours if the tea has not been applied to another source.

Tips & Warnings

• Add rock dust or brown rice flour to the brew to encourage beneficial fungi to grow in the tea. Though both will create a rich brew, worm castings will provide more beneficial microbes to your tea than standard compost. Use of additional air stones can increase oxygenation and decrease risk of tea turning anaerobic

• If tea does not have a pleasant earthy odor to it, it has not received enough oxygen and has turned anaerobic, possibly hosting pathogens dangerous for your plants. Be careful not to add too much compost to the mix, if there is too much organic matter in the tea from the outset, oxygen may be used up too fast and the tea may turn anaerobic.

References

• Pittsburgh Permaculture: Cheap Actively Aerated Compost Tea
• Soil Foodweb: Active Compost
• South African Gardening: Actively Aerated Compost Tea