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A Compost Tea Recipe To Boost Plant Growth

Are you searching for that ideal compost tea recipe?

Are you unsure which ingredients are used to feed which type of microbe?

Whatever the case, you need not worry; once you’re done reading the information on this page, you’ll be able to cater your compost tea recipe to your individual plant’s needs.

Did you know that the different plants in your garden, may need different types of compost tea?

That’s right, annual plants, such as vegetables, prefer a more bacterial-dominated soil, whereas, trees prefer a more fungal-dominated soil. Therefore, you would want to brew compost tea that is more bacterial-dominated for your vegetables, and tea that is more fungal-dominated for your trees.

To complicate things a little further, the type of tea you make, may also depend on the type of soil in your garden; so you must consider two variables: plant type and soil type. This may seem a little confusing at the moment, but just keep reading and soon it will all make sense.

sunflower after compost tea There is one thing to always remember when working with any compost tea recipe: mother nature is very forgiving. If, by accident, you apply a fungal-dominated tea to a bacteria-loving plant, you’re not going to harm it; However, your plant won’t benefit as much as if you had applied a bacterial-dominated tea.

Okay, let’s get started…

Various Teas for Various Plant Types

If you know what type of plant your are growing, than it’s easier to determine which ingredients to include in your compost tea recipe.

Type of Plant Type of Tea
Most brassicas Highly Bacterial
Vegetables, Grasses Moderately Bacterial
Berries Balanced Bacteria to Fungi
Deciduous Trees Moderately Fungal
Coniferous Trees Highly Fungal

What if your specific plant is not included in the above list? Simply find the type of plant that is most similar to the one you want to grow, and use it as a guide. For example, if you want to apply compost tea to a bed of perennial flowers, we would suggest using a more balanced (equal bacteria to fungi) compost tea recipe.

Without going into too much detail about specific teas for specific soil types, we would just like to point out two important things:

First, if you’re growing any type of plant in really sandy soils, you would benefit from applying fungal-dominated teas. Fungi help to build soil structure, which is always needed in sandy soils. Otherwise, we suggest you cater your tea to the type of plant, as shown in the table above.

Second, don’t be afraid to experiment. If you apply several bacterial-dominated teas, and nothing seems to happen, try a fungal tea for a couple applications.

The Most Important Ingredient

The most important ingredient in determining which type of tea you produce is your compost. Your compost will ALWAYS be the biggest factor in determining whether you brew a balanced tea, or a tea dominated by bacteria or fungi. If your compost doesn’t have any fungi in it, and you don’t add any, then there is no way your finished compost tea will have fungi in it.

So how do you make each type of compost?

Each of the different types of compost are determined by their initial ingredients. Bacterial-dominated compost begins with materials that have a lower carbon to nitrogen ratio (C:N); whereas, fungal-dominated compost begins with materials that have a higher C:N. Said another way, the more fungi you want in your compost, the more woody materials you are going to have to include.

use straw for compost ingredient For example, bacterial compost can be made using 30% dry straw (brown material), 45% alfalfa (green material), and 25% manure; whereas, fungal compost can be made using 45% dry straw, 30% alfalfa, and 25% manure. If you would like to create a more balanced compost, we suggest using 35% dry straw, 35% alfalfa, and 30% manure. To learn more about proper carbon to nitrogen ratios, please visit our compost ingredients page.

If you’re having trouble creating fungal-dominated compost, please see our expert tips at the bottom of the page.

3 Basic Compost Tea Recipes

Please note, the amounts indicated in the following recipes are intended for a 5-gallon brewer.

Balanced Compost Tea Recipe

    1.5 pounds of balanced compost
    (equal parts bacterial to fungal biomass)
    1.6 ounces of humic acids
    1 ounce of liquid kelp*
    1 ounce of soluble unsulphured black-strap molasses
*We’ve specified liquid kelp here, however, sometimes we like to add a tablespoon of kelp meal as well to provide surfaces for the fungi to attach too.

The black-strap molasses is great, because it naturally contains a number of beneficial minerals (e.g. potassium) that feed your microbes and soil.

Bacterial-Dominated Compost Tea Recipe

    1.5 pounds of bacterial-dominated compost (vermicastings work well)
    2 ounces of cane sugar
    1 ounce of soluble kelp
Bacteria love simple sugars, so feel free to add in a teaspoon of maple syrup, or even white sugar.

Fungal-Dominated Compost Tea Recipe

*We like to add yucca extract near the end of the brewing process, since it has a tendency to create a lot of foam. Also, you’ll want to make sure your yucca doesn’t have any preservatives, but does have a high saponin content.

Common Compost Tea Recipe Ingredients

Ingredient Feeds Ingredient Feeds
White Sugar Bacteria Maple Syrup Bacteria
Corn Syrup Bacteria Cane Sugar Bacteria
Molasses Bacteria/Fungi Fish Emulsion Bacteria
Fruit Pulp Bacteria/Fungi Fish Hydrolysate Fungi
Kelp Bacteria/Fungi Ground Oatmeal Fungi
Rock Dusts Bacteria/Fungi Yucca Fungi
Humic Acids Bacteria/Fungi Soybean Meal Fungi

Note – Fungi like to attach to the surfaces of various ingredients while they grow. Some of the above ingredients feed bacteria, and also provide surfaces for fungi to attach too (e.g. kelp).

Compost Tea Free Download

Five Free e-booklets

Interested in learning more about compost and compost tea?

What if we told you you’re just one click away from being able to download five free compost e-booklets?

All you have to do is click on the Compost Tea and Vegetable Gardening booklet to the right and read our Free Goodies page.

A Few Fungi Tips from the Experts

Tip #1

    If you want to increase the diversity of your compost tea, we suggest adding a cup or two of garden soil. Better yet, if your compost tea recipe calls for fungal compost, include a cup or two of soil from a nearby forest.

    By adding these additional soils, you’re ensuring your tea is inoculated with a wide range of soil microbes. These soils are like a biological catalyst, or compost tea activator.

Tip #2

    When we want to ensure we’ve got fungi in our tea, we will brew it, and then add spores of mycorrhizal fungi. Mycorrhizal fungi act as a wonderful inoculum to any fungal compost tea recipe. These fungi naturally form beneficial relationships with approximately 95% of all plant species. They aid in nutrient transfer to plants, and help to create better soil conditions. Here is a great site if you’d like more information on mycorrhizal fungi.

Tip #3

    We can’t claim this last tip to be our own. It comes from the incredible book, Teaming with Microbes, by authors, Jeff Lowenfels and Wayne Lewis. In it, Lowenfels and Lewis suggest you “give fungi a head start.” Since it can be difficult to get fungi to multiple (they do grow in size, just rarely in number) during the compost tea brewing process, the authors recommend growing them prior to the brewing process.

    To do this, you’ll want to moisten a couple cups of compost (just damp, not dripping wet), and then put it in a light-resistant container. Then grind up some simple proteins (fungal foods), such as oatmeal, and mix them in with the moist compost. Cover partially with a lid, and then place in a warm, dark area. We typically put ours under our sink, or above our fridge in a cupboard. After about 3 days, you’ll remove the lid, and find a bunch of fungal mycelia throughout the compost. You can now use this compost to brew your fungal tea.

Tip #4

    Don’t accidentally filter out your fungi (and nematodes) when straining your tea. When filtering your tea, be sure your screen is as close to 400 micrometers as possible. Paint strainers, from your local hardware store, work quite well for this function. Avoid using socks or pillowcases, since their fibers are too tight.

Our Ultimate Compost Tea Recipe

Please note, the amounts indicated in the following recipe are intended for a KIS 5-gallon brewer.

– 1/4 cup vermicompost (worm castings)
– 1/4 cup fungal-dominated compost
– 1/4 cup garden soil
– 1/4 cup forest soil
– 1.5 ounce of soluble unsulphured black-strap molasses
– 1 ounce of soluble kelp
– 1 ounce humic acids
– 1 ounce fish hydrolysate
– 3 tablespoons rock dust

[Updated Dec. 2011] – Due to the large variety of organisms and food sources in this tea, you will want to be absolutely certain that you have adequate aeration (i.e. dissolved oxygen) in your brewing system. Please click on the above link to learn more about the importance of aeration when brewing compost tea.

If you have any other questions or comments regarding a compost tea recipe, please contact us.