Compost Tea – What’s It All About?

Compost tea is a type of biological fertilizer known as ‘black gold’ or ‘liquid gold’ and used by gardeners around the world. It’s becoming increasingly popular by the day and many gardeners are now leaning towards using compost tea for their plants rather than the usual compost.

If you’re wondering whether compost tea is the right choice for your plants, then you’ve come to the right place! In this article, we’ll be taking a look at what compost tea is, how it’s made and its benefits and disadvantages.

What is Compost Tea?

Compost tea is what we get when we add compost to water. The nutrients, microorganisms and other compounds in the compost leech into the water. Humates which help plants to use the nutrients already found in the soil, in a more efficient way so having these in your compost tea is ideal.

Sometimes, people mistake compost tea for leachate. Leachate is a very dark fluid that you’ll notice leaking out from the bottom of your pile of compost. Leachate contains a lot of nutrients but it also does contain organisms that could make your plants sick, which means it won’t be usable in vegetable gardens.

What’s in Compost Tea?

Compost tea contains many different types or organisms. Here are some of the most common and most important ones:

Bacteria – certain types of bacteria help plants to grow better.

Fungi –fungi mycelium have fine threads that can easily spread over long distances so they capture nutrients and water from far away. They then bring these back along their fine threads and close to the plant roots so they can be used up by the plant.

Protozoa – these are extremely important for plants since they promote the production of the plant’s growth hormones. They also enhance the survival of the ‘good’ microbes and suppress pathogens.

Nematodes – nematodes are translucent and slender worms which play a big role when it comes to plant care. They turn organic matter into nutrients needed by your plants. Nematodes also eat up pests like root maggots and grubs.

Microarthropods – microarthropods are important in that they improve the ecology of the soil. They help organic matter in mulches and soil to decompose and can control the populations of dangerous organisms your plants don’t need.

How is Compost Tea Made?

Compost tea isn’t as difficult to make as you might think. However, it’s a process that takes up to 2 weeks. Compost tea is made by mixing cured or finished compost with water. Then, it ferments for anywhere from 24 hours – 2 weeks. The time it needs to brew depends on the type of compost and the brewing method you’re using.

Once the tea is ready, it’s straightened so that all solid material will be removed. What’s left is the liquid rich in the nutrients and microorganisms that your plants need. This liquid is applied to plant foliage or to soil.

To learn how to make compost tea step by step, check out our article on the subject.

Advantages and Disadvantages of Compost Tea

Before you decide on buying or making your own ‘tea’ for your garden, it might be a good idea to weight the pros and cons so you can be sure that you’re making a well-informed decision.


  • Improves soil tilth – tilth is important since it provides ideal conditions for root proliferation and seed germination
  • Helps the soil to retain its nutrients
  • Enhances the availability of nutrients
  • Suppress root diseases – unlike solid compost, compost tea gets all the way down to the roots of your plants. It creates a physical barrier against disease.
  • Convenient to handle
  • Improves plant growth
  • Minimizes the need for synthetic fertilizers – if the quality of your tea is excellent, you can even stop using synthetic fertilizers entirely.
  • It’s completely organic. Rather than killing the life of your soil using chemicals, you can turn it into a thriving environment for your plants.


Although compost tea has many advantages it also has a some disadvantages that you might want to take into consideration.

  • Contains less carbon compounds which are essential for the ‘good’ microorganisms
  • Quality can vary depending on the type of compost
  • Cannot be stored for later – once the ‘tea’ is brewed it must be soon as soon as possible. If you store it for a long period of time, the tea will become anaerobic. This means that that it kills all the ‘good’ bacteria that it contains.
  • It’s a weaker form of fertilizer since it provides a much smaller amount of nutrients and microorganisms than actual compost.
  • The benefits mostly depend on the quality of the compost that’s being used to make the tea.

The Take Away

Now that you have all the information you need on compost tea, it’ll be easier to decide whether you want to use it in your garden. If you’d like to give it a try, don’t worry because it’s not going to cause any harm to your garden and if you feel it doesn’t work out, you can switch back to what you were using before. After all, it doesn’t hurt to try something new!

We hope that our article was useful and contained everything you needed to know!