How to Make Compost Tea: The Organic Energy Drink for Plants
How to Make Compost Tea
Homemade compost tea is a concentrated solution of garden compost dissolved in water. The high-energy liquid makes it easy for the organic gardener to apply the beneficial microbes and other nutrients right where the plant needs it most—directly on the plant's leaves and into its root system. And you can apply this organic fertilizer with each watering to grow larger and healthier plants.
Many gardeners already reap the benefits of using compost to enrich the soil in their gardens. Packed with organic nutrients, garden compost helps to promote strong plant growth and healthy root systems. Unlike synthetic fertilizers that dissipate quickly, mixing organic materials into the dirt improves the composition of the soil, slowly releasing nutrients for the plants to absorb over longer periods of time. Brewing a homemade nutrient-rich solution is a simple process of mixing compost, water and air to stimulate the growth of beneficial microbes. The organic solution is then poured around the base of the plant, or you can use a garden sprayer to coat the leaves with a healthy dose of homemade organic fertilizer. And it's cheap!
While there are many different models and sizes of commercial products available, making a simple and effective brewing system is easy and requires just a few common materials. All you need is a five-gallon bucket, some plastic tubing, an inexpensive air pump and a little garden compost.
The Compost Tea Brewing System:
Things You Need:
- Five-gallon bucket
- Aquarium air pump
- Plastic tubing
- Air stone
- Garden compost
- Molasses (optional)
There are two basic methods for making compost tea. The first is the fast and easy approach: simply stir a small amount of compost into a bucket of water and use immediately. A variation of this method suspends a porous bag filled with compost into a bucket of water, then leaves the compost bag to steep for a few hours before feeding the plants (an old onion bag works well).
The second method calls for using a simple brewing system. Compost is stirred into a bucket of water, then aerated to stimulate the population explosion of beneficial microbes. Continually circulating the water also prevents stagnation.
- Fill a five-gallon bucket until two-thirds full with water, and then add a shovelful of loose, quality garden compost. Stir vigorously to create a liquid solution.
- Allow the solution to settle for about 15 minutes. Some of the compost will come out of solution, and the silt will settle at the bottom of the bucket. Attach the air stone to the plastic tubing, place it in the bucket, and turn on the air pump. The air stone oxygenates the water to stimulate the microbe population growth. Use a small spring clamp to secure the tubing to the edge of the bucket and to hold the air stone in place below the surface of the water.
- Optionally, add a cup of molasses to the mixture to further stimulate and feed the exploding the microbe population.
- Allow the solution to brew for at least 24 hours and up to 48 hours. Since microbes require oxygen for survival, it is important to continue the aeration non-stop throughout the compost tea brewing process. Should the growing microbial population exhaust the oxygen supply, the mixture becomes anaerobic (depleted of oxygen).
- Strain the mixture to remove any larger particles, and then apply the solution directly to the plants and leaf surfaces with a watering can or garden sprayer. Many garden sprayers have very small spray nozzles that might clog, so thoroughly strain the liquid before using in a garden sprayer.
Our Compost Bin
In its simplest form, a compost bin is an enclosure for containing garden waste and kitchen scraps while they decompose. Though a compost bin is not necessary—you can just make a pile in an out-of-the-way area of the yard and leave the material to break down—a bin creates a barrier and makes it easier to control the pile.
Making a compost bin is an easy DIY project and a good way to recycle old building materials. An enclosure of garden fencing makes an effective containment system, and our neighbor made their bin from several old shipping pallets.
Our compost bin reuses several discarded sections of railing from an old deck. The railings are positioned to form two open enclosures and then wrapped with leftover pieces of garden fencing and chicken wire.
Using the two-bin system is simple: fresh kitchen and garden waste and grass clippings are tossed in one side along with the cleanings from the chicken coop, goat pen and guinea pig and rabbit cages. The material is turned occasionally and left to break down. In a couple of months, the material in this bin is ready for use, and we start filling up the other bin. After another few months, we repeat the cycle of alternating between the bins for depositing fresh material into one bin and harvesting composted soil from the other bin. We sift the material through a rough screen before using, and this helps to separate any rough debris from fully composted black gold.
As you can see from the photos, we let the chickens scratch through the bins. Though they make a mess by spreading the materials everywhere, they also help to aerate and turn the compost pile.
The Dos and Don'ts of Composting
There is a lot of nitrogen and carbon-based waste around the house and garden that is safe and suitable for the compost bin, and here are a few tips to help turn those kitchen scraps and yard waste into black gold for the garden:
- Save Your Kitchen Scraps: Fruit and vegetable scraps are high in nitrogen. Save the peelings, seeds and wilted greens for the compost pile, along with egg shells, used coffee grinds and filters, and spent tea bags. Clean out the refrigerator and toss those old and wilted veggies into the compost heap.
- Add Leaves and Grass Clippings: Mixing in fresh, green grass clippings adds moisture and nitrogen to the compost pile, while the fallen leaves and spent annual flowers add the brown carbon-based matter.
- Locating the Compost Bin: The compost pile is not an overly attractive garden feature, so select a site for the compost bin that is conveniently located for easy access but located an in area that is screened from view. Shady areas work as well as a sunny location, especially in warmer areas where the sun can dry out the compost pile.
- Got Chickens, Rabbits, Guinea Pigs or Hamsters? The dirty pine shavings from cleaning the cages of herbivore pets are perfect for the compost pile. Chicken manure adds a lot of nitrogen to the mix; just make sure that the compost pile cooks thoroughly to break down any pathogens that might have passed through the animals. Used by itself, the high nitrogen content in chicken manure can burn tender plants. But the pine shavings from the chicken coop are high in carbon-based matter; mixed together, the chicken manure/pine shaving combination balances the nitrogen and carbon levels.
- Mix It Up: Turning the compost aerates the pile and helps the organic matter to break down faster. A pitchfork is my tool of choice for this chore, but a shovel also gets the job done.
- Add Some Variety: Avoid tossing too much of the same type of organic matter into the compost pile. With the chicken coop and guinea pig cages, our pile has a tendency to fill up with lots of pine shavings. Mixing in fresh grass clippings along with raw vegetable and fruit peelings and some of the fully composted materials helps to mix up the elements and speeds up the decomposition and composting process.
- Keep It Moist: During the heat of the summer, the compost pile tends to dry out, and this slows the composting process. A few buckets of water or a sprinkling from the garden hose helps to keep the pile moist between rainfalls. At the other extreme, don't let the compost pile stay too wet, which encourages the growth of smelly mold and mildew.
- Clean Out the Wood Stove: Moderate amounts of wood ash is fine for the compost bin, but avoid any coal ash or the remnants from the charcoal grill that do not break down easily and can be high in iron and sulfur.
- Bigger is Better, but Only to a Point: Too small of a pile inhibits the amount of heat generated by the decomposing organic materials, but too large a pile takes too long to break down and is more difficult to turn over for aeration. A compost pile about 3 foot by 3 foot square is just about the ideal size for a compost bin.
Do not add any of the following items to your compost pile:
- No Meat, Bones or Other Animal By-Products: Besides attracting varmints and other unwanted pests, rotting meat scraps and bones give off unpleasant odors. Do not compost dairy products, either, which can attract rodents and other unwelcome visitors.
- Leave Out the Big Sticks: Small twigs and woody plant stems are okay, but large sticks can take a long time to break down into usable compost. Remove the rocks, too.
- Avoid Diseased Plants: Toss any diseased plants into the trash, and keep them out of the compost pile. Do not compost any toxic plants (poison ivy comes to mind), including many types of house plants that can also be toxic. Also, do not compost any grass clippings or other plant material that was treated with herbicides or pesticides.
- No Kitty Litter Here: Do not empty the litter box into the compost pile. Dog and cat feces contain pathogens that can be harmful to humans.
- Hold the Cardboard: Though many composting experts may disagree, I have not had success with composting cardboard and newsprint. Instead, use fallen leaves for the brown carbon layers and send the newspaper and cardboard to the recycling center.
Making Compost Tea
Do You Compost?
The 2-in-1 Compost Tumbler
A compact composter works great in my application. Most of our raw materials for the compost bins come from the chicken coop, the goat pen and the guinea pig cages. We take smaller amounts from the compost bin and feed it into the tumbler where it quickly turns into black gold—perfect for the container plants and top dressing around freshly planted veggies.
Solid construction and an easy-to-spin design are two good reasons to consider a compost tumbler. When shopping for a compost tumbler, look for a design that turns kitchen scraps into dark, rich compost within a few short weeks and includes a built-in base to collect the liquids into a nutrient-rich compost tea.
Let's face it: Saving kitchen scraps is a messy chore. Having a convenient place to toss those kitchen scraps—with a lid to contain any unpleasant aromas—and we're more likely to save those fruit and veggie trimmings for the compost heap. Add a handle and an easy-to-clean stainless steel container in an attractive package, and you have a compost pail that you will actually enjoy using. Sure beats that old coffee can.
Worms break down kitchen scraps and other organic matter into an incredibly rich compost. Simply add the Red Wriggler worms into a composter designed for worm composting, add some veggie peelings and other greens, and let the worms do their thing. The result is nutrient-rich compost to spread in your garden or brew into compost tea.
Our Compost Bin - A Simple Two-Bin System
Questions & Answers
© 2012 Anthony Altorenna