How to Make Compost Tea (and What It Can Do for Your Garden)

Compost tea is a rich brown liquid is extracted from compost to deliver nutrients and beneficial microbes directly to your plants. Because the liquid is delivered to the soil through irrigation, watering, or spraying, it works faster than traditional layers of solid compost.

And it’s something gardeners feel strongly about.

“Compost tea is the cure for what ails you,” says Andy Thewlis, Farm Manager at The Inn at Little Washington. “It’s a magic potion that can be brewed with ease at home. An actively aerated tea is rich with beneficial microorganisms that support soil and plant health. Think of it as kombucha for your soil.”

Want to add this magic potion to your plants? Here’s how to make compost tea at home, as well as the benefits it has on your garden.

What Is Compost Tea?

Compost tea is the liquid extract that comes from steeping compost in water. This makes a concentrated version of compost that’s packed with nutrients, microorganisms and microbes, and is used as a natural liquid fertilizer to boost soil health and plant growth.

“The idea is that steeping your compost and creating a liquid compost will help the nutrients reach plant roots more effectively compared to regular compost, promoting better root health,” says Alex Kantor, owner at Perfect Plants Nursery.

Want more gardening tips? Sign up for our free gardening newsletter for our best-growing tips, troubleshooting hacks, and more!

Benefits of Compost Tea on Plants

Compost tea creates a healthier environment in the soil—and everything comes back to the soil when gardening.

“The soil is the stomach of the plant,” Thewlis says. “With compost tea, microorganisms break down minerals and organic matter for plant uptake.”

By using compost tea, you’re aiding your plants in digesting all of the good nutrients and minerals they need. This leads to benefits including stronger root systems, faster growth, more abundant flowering, and, if you’re growing fruits or vegetables, a larger harvest.

“With the use of compost tea, I see accelerated growth and heightened immune responses in my plants,” Thewlis says.

How to Make Compost Tea at Home

Good compost tea starts with good compost, and compost is easy to make at home. You can either start a compost bin outside or in your home. Everything from food scraps to yard waste to coffee grounds will go inside your compost bin, and the compost should be ready within two months to use for either non-aerated or aerated compost tea.

How to Make Non-Aerated Compost Tea

Non-aerated compost tea is the easiest method to make at home.

1. Put one to two cups of compost in a mesh bag—think of this as a tea bag.
2. Set the compost bag into a bucket and fill with one gallon of clean water.
3. Put the bucket in a dark closet or basement. Stir once daily.
4. After one week, remove the compost bag, and you have compost tea.

How to Make Aerated Compost Tea

Aerated compost tea is the same as non-aerated compost tea but on the fast track. It’s made the same way as non-aerated compost tea, but with one extra step that speeds up the process: placing an aquarium bubbler in the bucket along with the water and compost bag.

Because the bubbler dissolves oxygen into the mixture, it quickly “steeps” it. You’ll have finished compost tea in 48 hours rather than two weeks.

How to Use Compost Tea

While most fertilizers are applied seasonally, compost tea should be applied as often as once a week. It’s applied around the base of the plant, directly to the soil.

“When using compost tea, make sure to direct the water toward the roots and soil of the plant rather than pouring it on top of edible fruits, flowers, or vegetables,” Kantor says.

Thewlis adds that you can use it as a foliar spray, which is when it’s spray directly on the leaves. This can help with disease and pest control.

3 Mistakes When Making and Using Compost Tea

Making compost tea is a straightforward, simple process, but there are a few places it can go awry.

Letting Compost Tea Sit Too Long

If you let a compost tea sit without stirring or aerating, it can go bad in a matter of days.

“Compost tea should have more of an earthy coffee smell, never a rancid moldy smell,” Kantor says.

Using Unclean Water or Equipment

While you want good microorganisms to start brewing, you do not want bad ones. If you use water that’s been used elsewhere or a bucket that hasn’t been cleaned, you could invite in bacteria that will throw off the nutrient-rich balance.

Adding Sugar

Some recipes call for sugar in a compost tea brew, but that can spark growth of bad bacteria like salmonella.