How to Make Compost Tea - Backyard Boss
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How to Make Compost Tea

It is no secret that compost is a beneficial addition to your garden. On top of that, it is a sustainable way to handle waste, whether it is from your kitchen or the dying plants and grass clippings in your yard. In fact, you can even make compost tea out of organic matter to make the most of your compost. Just remember it is a drink for your plants and not you!

Are you wondering how you can make your own compost tea? While the process requires a bit of time and attention, it boasts many benefits for your garden. Learn how you can turn your leftover dinner scraps into a solution that waters and fertilizes your yard all at once!

What is Compost Tea?

Compost tea
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Compost tea is cured compost diluted in water and fermented for some time. Essentially, it is the liquid version of compost. It is not leachate, the dark fluid that leaks out of compost, which contains bacteria that can cause illness, and you shouldn’t use it in vegetable gardens. It contains beneficial nutrients and microbes (bacteria, fungi, protozoa, nematodes), meaning you don’t have to rely on expensive chemical treatments.

Pros and Cons of Compost Tea

person holding a watering can near plants
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Since compost tea is a liquid, it doesn’t take up the same space in soil that compost does. The fact that it is a liquid also means that the plants can receive the beneficial nutrients more quickly. Speaking of nutrients, the nitrogen, phosphorus, and potassium present in tea are great substitutes for fertilizer. The tea is also easier to apply since you need to pour it rather than mix it into the soil as you would with compost.

The quality of the compost tea depends on the quality of the compost. Therefore, the effectiveness of the product can be difficult to predict. Compost made from manure is generally best, while compost with high salt levels might do very little for your plants. If this is the issue, you can use other natural methods to fertilize your plants. You also must use the tea immediately after you brew it because it turns anaerobic over time and kills beneficial bacteria.


  • Provides essential nutrients such as nitrogen, phosphorus, and potassium
  • Improves soil structure and fertility
  • Easier to apply than compost


  • It can be difficult to predict the quality of the compost tea
  • You must use it immediately after brewing
  • The brewing process can take a few days

Tools You’ll Need

indoor compost
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To properly make compost tea, there are a few tools you’ll need.

  • Large bucket (around 6 gallons)
  • Fish tank air pump (optional)
  • Mesh bag, burlap sack, or strainer
  • 5 gallons of water
  • 3 cups of mature compost
  • 2 tablespoons molasses (optional)
  • Plastic spray bottle or watering can
  • Baking soda
  • Scrubbing brush

How To Make Compost Tea: Step-by-Step Guide

Step 1: Preparations

Woman emptying kitchen waste on to a compost pile with layers of organic matter and soil
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The first step in making compost tea is preparation. Start by filling a 6-gallon bucket with 5 gallons of water. If you are using water with chlorine, remove it by allowing it to sit in an open container for 24 hours. You can also place a fish tank air pump in the bucket and allow it to aerate for 2 hours.

Step 2: Add Compost

soil and yellow spatula
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Place three cups of mature compost in either a mesh bag or burlap sack and place it in the bucket. You can also place the compost directly in the water and use a strainer to remove it from the tea later. Optionally, add two tablespoons of molasses to feed the microbes.

Step 3: Let it Brew

Compost bin made of recycled plastic next to beautiful vegetable garden with ripe tomatoes. Recycling, green, concept.
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With the water and compost in your bucket, it is time to let the brewing process begin. There are two ways to do this:

  1. Depending on the fish tank air pump you have, submerge the pump itself or the tube attached to it. Switch it on and allow it to aerate for 24 to 48 hours. The longer you aerate it, the more nutrients the compost will have. But, if you do this for longer than two days, the compost may decay.
  2. If you don’t have an aerator, do not put the compost in a bag. Stir the water and compost for about two minutes right after setting it up, and then do continue to do so twice a day for seven to 10 days.

No matter which method you use, the tea should have an earthy scent and resemble coffee or tea when it is ready. If it smells rotten, it has gone bad, and you shouldn’t use it.

Step 4: Filter it Out

Spray bottle
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Use your strainer to filter out the compost, or remove the bag with the compost and wring it out. Pour the compost tea into a plastic spray bottle or watering can. Also, remember to clean your spray bottle or watering can with warm soapy water to remove any residual chemicals from previous uses.

Step 5: Using Compost Tea

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Use the tea as soon as possible once it is ready. You can dilute the tea 50/50 with clean water if you’re using it on your lawn or spray directly on the soil to feed plants, shrubs, and trees. Use about a cup of tea per plant or roughly 5 gallons for your lawn.

If you start making your tea before preparing your dinner, you can apply it to your garden the next evening or the day after. Apply it to your lawn and plants as often as you would fertilizer. As a general rule of thumb, once or twice a month is good during the growing season (spring through fall).

Apply early in the morning or evening after the sun goes down to prevent evaporation, just as when watering plants. Also, avoid applying compost tea if your plants don’t need watering, as it has the same effects and you risk overwatering them.

Don’t forget to clean your equipment after using compost tea. Scrub your items with baking soda and water, and rinse thoroughly with water. Store all the equipment in the bucket for easy access when you make the tea again. You can also mix the used compost into your garden or add it back to your compost pile.

Quali-tea Compost

Compost is beneficial for your garden in many ways, but so is compost tea. While it takes a little time to make, it applies beautifully to your garden and effectively replaces fertilizer. Plus, it hydrates your plants at the same time! It is easy for the plants to soak up the liquid, effectively absorbing nutrients quickly.

Do you know of any tips or benefits for using compost tea? Share in the comments below!