How to Oxygenate Compost Tea

Compost's rich nutrients can be harnessed through the use of compost tea.

When in a pinch, compost tea can be brewed without oxygenation--compost and water is simply left in the sun or on the stove to infuse. However, unoxygenated compost tea is not genuine compost tea. Through forcing oxygen into the tea, aerobic microorganisms are allowed to flourish, versus the undesirable anaerobic microorganisms that can develop in environments devoid of oxygen. Through oxygenation, the work of flowing creeks and babbling brooks is simulated to add benefits to your garden or farm for which there is no substitute.

Difficulty:

Moderate

Instructions

Things You'll Need

• 75-gallon plastic barrel with bung
• Two or more fish tank pumps
• Vinyl tubing
• Small container with hook
• Compost
• Pantyhose
• Two cups of molasses flakes
• Extension cord (as needed)

1. Place the barrel where an electric outlet is accessible, as close as possible to where the finished compost tea will be used.

2. Attach the vinyl tubing to the fish tank pumps. Tubing should be long enough to reach almost to the bottom of the barrel.

3. Place the pumps inside a waterproof container, and hook the container onto the lip of the barrel. The pumps may be hooked inside the barrel to protect from weather.

4. Fill pantyhose with compost to create a compost "tea bag." This is best done with one person holding the pantyhose open, while another person scoops the compost and inserts it into the pantyhose with a trowel. Stretch the pantyhose horizontally, not vertically. It should fit about a gallon's worth of compost.

5. Tie the pantyhose closed and hang it on the inside of the barrel.

6. Fill the barrel with water, and add the molasses flakes.

7. Plug the pumps into an electrical outlet. Use an extension cord if necessary.

8. Leave the compost tea "brewing" for two days. It is then ready for use in the garden. Use within five days, as the tea may ferment.

Tips & Warnings

• When using compost tea on food crops, apply a full concentration solution once a day in addition to regular watering. Use about 2 gallons per 40 square feet. For use on seedlings, dilute the compost tea to 50 percent concentration and use as a regular watering.

• Always practice caution when using electrical devices outdoors and in proximity of water. Read the manufacturer's safety guidelines for the fish tank pumps.

References

• University of Illinois: Composting for the Home Gardener
• Oregon State University: Plans for a Homemade 25-Gallon Compost Tea Brewer (PDF)
• University of Florida Institute of Food and Agricultural Sciences: How to Use Compost