Compost Tea: How to Make This Garden Elixir

“Warm, frothy, and chocolate brown” sounds like a tasty drink for a cold winter day, doesn’t it? While you wouldn’t want to drink this particular elixir, your plants sure do! Here’s how to make your own compost tea.

If compost is garden gold, compost tea is the liquid version. It can be applied like regular fertilizer, or sprayed on plant leaves as a foliar feed (be sure to spray in the evening, and test on a small patch for 24 hours first to make sure it doesn’t burn the leaves of whatever plants you’re applying it to). It provides loads of nutrients, in liquid form.

Here are directions for making your own tasty compost tea for your garden, courtesy of

Compost tea is simply compost in a liquid form. Just like a fine oolong, you take a pinch—or in this case a shovelful—and steep it in water. The nutrients leach out and you shower your plants with them. The roots drink them up and even the leaves can absorb them through their stomata, the tiny pores in leaf tissue.

But the real excitement around compost tea has less to do with nutrients (which occur in very low concentrations in the liquid) and everything to do with the microorganisms it contains, especially beneficial bacteria and fungi. It’s a bit like the concept behind the probiotics you would take for intestinal health, but applied to plants. By coating the roots or leaves of a plant with beneficial bacteria, the theory is that the bad guys—diseases like root rot or powdery mildew—can’t gain a foothold.


How to Brew Your Own

….The easiest way to oxygenate the brew is with a basic aquarium aerator (the type that connects to air stones with poly tubing) that can be found at any pet supply store.

Step 1: Place three or four air stones in the bottom of a five-gallon bucket and connect the tubing to the aerator….

Step 2: Fill a five-gallon bucket one-third of the way with finished compost….

Step 3: Add water to the bucket to within 2 or 3 inches of the top. It’s important not to use chlorinated municipal water, as the chlorine will kill the microbes. Rain water or well water are good options….

Step 4: Run the aerator in the compost slurry for two to three days, stirring the mix occasionally with a stick to encourage the substances in the compost to leach into the water.

Step 5: Filter the solids from the tea before using. If you’re applying the compost tea only on the ground, a filter with large holes is sufficient (a burlap bag will do). If you want to spray it on the leaves…, you’ll need a finer filter, such as panty hose or an old pillow case. Simply hold the filter over another five gallon bucket and pour the mixture through it.

Step 6: Dilute the tea before applying at a ratio of one part tea to five or 10 parts dechlorinated water.

Step 7: Apply within several hours of turning off the aerator to prevent the mixture from becoming anaerobic and losing its potency. A spray bottle is sufficient for applying the tea to individual plants, but you’ll need a backpack sprayer…if you’re going to apply it to the entire garden.

For more tips on making your own compost tea, visit


Rose S.

An avid gardener since childhood, I love sharing my passion for gardening with others! I have gardened in a number of different climates and settings, from large fenced garden plots, to tiny patio and container gardens, and I firmly believe that everyone can learn to grow at least some of their own food - no matter where you live. Growing your own food can help you take control of your own health and food supply, and there has never been a better time to get started!

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