Mixing compost into flower and vegetable beds is an important part of any gardening program, but why stop at adding millions of beneficial bacteria to the soil when you can add billions?
By mixing that earthy concoction with water and allowing it to steep, you can create a beneficial "tea" loaded with nutrients that plants love.
It improves compost's usefulness, too. Compost tea can be used as both a foliage spray and a soil drench. When sprayed on a plant's leaves, the tea's soluble nutrients give the plant a healthy boost and help control diseases such as black spot on roses or early blight on tomatoes.
As a soil drench, compost tea builds healthy soil by increasing microbial activity and providing soluble nitrogen, potassium, and phosphorus.
Compost tea can be brewed by either of two methods: passive and aerated.
Passive tea is a compost extract such as the one farmers have used for hundreds of years. Small batches can be made by filling a burlap sack with compost and steeping it for about two weeks in a bucket filled with water, using a 1:5 ratio of compost to water. The compost extract should be used immediately for best results.
The second brewing method is aerated tea and uses an inexpensive aquarium pump to keep oxygen circulating in the compost and water mixture. This method significantly increases tea's beneficial bacteria, research shows.
Gardeners can buy ready-made compost tea, but it's less expensive (and more fun) to brew up a batch using your own homemade compost.
FOR AERATED TEA YOU'LL NEED:
- Two 5-gallon buckets
- 5-8 feet aquarium tubing
- 1 aquarium-size pump large enough to run three air bubblers
- 1 gang valve to split tubing into three outlets to divide the air supply into several streams
- 3 air bubblers
- Decomposed compost (do not use manure)
- 1 stirring stick
- 1 ounce unsulfured molasses
- Burlap sack, cheesecloth, or old nylon stocking
- Run the bubblers in a bucket of water for at least an hour to remove the chlorine.
- Fill the second bucket one-third to one-half full with compost.
- Attach one length of tubing to the pump and the other to the gang valve.
- Cut three lengths of tubing to reach from the bucket rim to the bucket bottom.
- Connect each piece of tubing to a port on the gang valve; connect each end to a bubbler.
- Place the valve on the rim of the bucket and bury the bubblers under the compost.
- Fill the bucket with water; start the pump.
- Add molasses to the mixture; stir well. Reposition the bubblers if needed.
- Aerate tea for three days; stir several times each day.
- Unplug the pump and let the mixture settle for about 30 minutes before straining through the burlap into a bucket.
For best results, plan the three-day brewing cycle so that you can apply the tea as soon as it's ready. Be sure to sanitize the equipment before making your next batch of tea.
Jodi Torpey writes and gardens from her Denver home where she regularly hosts compost tea parties for her favorite plants.