Are you looking to add organic amendments to your garden? Perhaps trying to put all that copious amount of fragrant compost to use? Or are you seeking to make your ancestors proud with your mad plant-wizardry skills? Well… probably not the last one. Yet, look no further than the nutrient-rich miracles of compost tea. But what exactly is compost tea? And, how do you make compost tea? In this post, we dive into all the elements (and history!) that goes into this plant food elixir.
What is Compost Tea?
Well… pretty much what it sounds like. But what would be a less than appetizing drink for humans, makes for a much loved one in your garden.
Compost tea is a liquid extract of compost containing beneficial bacteria, fungi, and nutrients. It acts as a natural fertilizer and soil conditioner, enhancing plant health and reducing (ideally, eliminating) the need for chemical fertilizers.
Compost tea (especially of the aerated variety) gained a lot of traction with the gardening community in the late ‘90s due to Dr. Elaine Ingham and her work developing The Soil Food Web. (Check out their website to geek out on even deeper soil biology stuff: Dr. Elaine’s™ Soil Food Web School - Regenerating Soil - Regenerative Agriculture Courses)
In truth, compost tea has been around long before that. Many traditional farming cultures, like those in China, India, and Egypt, have used liquid extracts of compost or manure to fertilize crops for centuries. Farmers would soak manure, compost, or plant matter in water to create nutrient-rich solutions. This includes the increasingly popular technique of Korean Natural Farming, which you can read more about here: Exploring the Essence of Korean Natural Farming (KNF): Harmony in Soil and Soul
Before you start brewing compost tea, it’s important to understand the two main types—Aerated Compost Tea (ACT) and Non-Aerated Compost Tea (NCT)—also known as a compost extract. They differ in how they’re made, their microbial content, and their effects on soil and plants.
ACT is made by bubbling oxygen into a compost-and-water mix for 24–48 hours. This encourages beneficial aerobic microbes that support soil health, nutrient cycling, and disease resistance. It’s great for giving your soil a strong microbial boost.
NCT, or compost extract, is made without adding oxygen—just steeping compost in water. But timing is key: only brew it for 12 hours or less. Any longer and it can go sour, fostering anaerobic microbes that may harm rather than help your soil. Once it sours, it’s no good—toss it and try again.
Both have their place depending on your goals and setup. ACT is ideal for long-term soil health, while NCT offers a quick, low-tech nutrient and biology boost—just keep it fresh!
Compost Tea Recipes
Now to the exciting part, getting your hands dirty. Learn how to make both kinds of compost tea for your garden.
Aerated Compost Tea (ACT)
For Maximum Microbial Life
For This Simple Recipe You’ll Need:
- A 5-gallon bucket
- Filtered or dechlorinated water (you can let tap water sit 24 hrs or use rainwater as well)
- Fine mesh compost tea bag (burlap or nylon stocking would also work)
- 1-2 cups of high-quality biocomplete compost
- 1–2 tablespoons molasses (microbe food!)
- Aquarium air pump + air stone
Steps:
- Fill the bucket with water.
- Place compost in a porous bag (burlap, nylon stocking, fine mesh compost tea bag) and submerge it.
- Add molasses.
- Drop the air stone into the bucket and run the air pump and bubble the tea for 24–48 hours.
- Strain and use right away.
Note: Its best to make the right sized batch fresh and use it all right away! If you must store it, store it in the fridge for up to 1 week, but label it well!! Just know that the potency of the tea starts to drop immediately, and after 1 week, the quality and quantity of microbial life is seriously depleted, and that was the whole point!
Non-Aerated Compost Tea (NCT)
Easier but Less Potent
For This Simple Recipe You’ll Need:
- A 5-gallon bucket
- Dechlorinated water
- Fine mesh compost tea bag (burlap or nylon stocking would also work)
- 2–3 cups of high-quality biocomplete compost
Steps:
- Fill the bucket with water.
- Place compost in a porous bag (burlap, nylon stocking, fine mesh compost tea bag) and submerge it.
- Let it steep for up to 12 hours, stirring occasionally.
- Strain and use right away.
The Next Level
Want to kick things up a notch? There's tons of great information out there and suppliers who can help you take your compost tea brewing to the next level!
Some Additional Ingredients to Consider Include:
- Worm castings
- Kelp meal
- Humic and Fulvic Acids
- Fish Hydrolysate
Here at The Farm Connection, we are brewing a SUPER tea for our plants using the above ingredients, thus bringing those benefits to YOUR gardens when you plant our plants! Watch our little video of our new compost tea brewer in action here: https://www.facebook.com/share/v/18kkZcAEXs/
We used the design and recipe (a little adjusted for our own purposes and goals) from composttealab.com. They've got great information so be sure to check them out: Brewing Compost Tea by TeaLAB
FAQ
What can I use compost tea on—and what should I avoid?
Use compost tea on:
✅ Vegetable gardens (roots and leaves—ACT only for foliar!)
✅ Fruit trees and berries
✅ Perennial plants and shrubs
✅ Native plants and pollinator gardens
✅ Lawns and pasture
✅ Seedlings and transplants (diluted)
✅ Compost piles (to boost microbial activity)
Avoid using compost tea on:
🚫 Leafy greens or herbs right before harvest (especially if you're not sure of compost source—better safe than sorry)
🚫 Any plant if the tea smells sour or off (it’s likely anaerobic and can harm soil or plants)
🚫 Succulents and most houseplants
Tip: When in doubt, test a small area first. Healthy compost tea should smell earthy, not funky. And always use dechlorinated water when brewing or applying!
Can I make compost tea from comfrey leaves or weeds? Doesn’t that work too?
Yes—just a different kind of “tea”! Brewing a liquid from comfrey leaves, weeds, or other plant material does work, but it’s not the same as compost tea made from finished compost. What you’re making is typically called a plant tea or fermented plant extract, and it’s more about feeding your plants nutrients than adding beneficial microbes.
To make it, chop up fresh plant material (like comfrey, nettles, dandelion, or weeds), soak it in water (ideally in a bucket with a lid) for 1–2 weeks, and stir occasionally—it will smell bad! Once it’s broken down, strain and dilute the liquid before applying it to your garden as a natural fertilizer.
These teas are great for giving plants a quick nutrient boost, especially leafy greens, fruiting crops, and perennials. Just remember: this is not the same as microbial-rich compost tea. Plant teas feed the plants directly, while compost teas are brewed to inoculate soil with living biology and support long-term soil health.
Now What Do I Do?
Choosing between ACT and NCT really comes down to your goals, time, and tools. If you’re looking to build long-term soil health or protect your plants with a foliar spray, go for ACT. If you need a quick nutrient boost and don’t have the gear, NCT (or compost extract) is your go-to—just keep it fresh.
Either way, compost tea is a great way to support living soil and resilient plants. Start where you are, use what you have, and keep learning as you grow.
And that’s it! Compost tea is a super simple, time-tested way to give your plants a natural boost. Whether you go all-out with aeration or keep it low-key, your garden will thank you. Leave me a comment, if you decided to make a few gallons, and let me know how it went!