How to Make Worm Casting Tea – Vermicomposting Tea for your Plants and Garden

Worm-casting tea is an effective mild fertilizer for your garden and plants. It is a budget-friendly way to enrich your garden, especially if you have your own worm farm. Use our guide to make worm tea with a recipe and detailed instructions.

How to Make Worm Tea For Your Plants and Garden

If you are a frequent visitor at the Garden Bench Top, you will know we have our worm castings farm and are huge fans of worm poop (aka worm castings).

And if you are researching how to make worm poo tea, then we are guessing you are too!

credit: buzzfeed

However, to give you the correct instructions for making your worm castings tea, we need to establish how you intend to use the worm tea.

In this guide, we will be providing different recipes for various gardening purposes:

  1. worm tea for seedlings
  2. worm tea for container plants
  3. worm tea for more extensive gardens

So, if you’re as excited about worm tea as we are, let’s get our hands dirty!

How to Make Worm Tea (Worm Juice): The Method

The method for making the worm castings tea is essentially the same. We simply adjust the ratios and quantities of ingredients for different purposes.

So in this section, we’ll discuss the main technique for making your worm manure tea.

Similar to when you make yourself a nice cup of tea in the morning, the central concept of vermicompost tea is to steep worm castings in water to form a liquid fertilizer.

Only we’ll not be sipping on this one while we dig into a good book.

credit: tenor

Required Equipment

  • large container for steeping (size will depend on how much worm tea you intend to make)
  • dechlorinated water (filtered or rainwater)
  • worm castings
  • molasses (optional)
  • muslin cloth, dish towel, or panty hose (to act like a tea bag lining) or wire filter

1. Preparing Your Worm Tea

Besides gathering all the equipment detailed above, the main item you may need to prepare ahead of time is the water, particularly if you do not have a ready source of dechlorinated water, like a rainwater tank.

The good news is you can use tap water for worm casting tea.

To do this, on the day before you intend to make up the worm tea, fill your container with tap water and leave it for 24 hours. During this period, the chlorine will evaporate, and you will end up with water safe to use in your garden.

2. Create Your Worm Castings Tea Bag

Place the required amount of worm castings (refer to our recipes below for the correct quantity of worm castings) into the center of your cloth.

Pull each corner of the cloth up to meet each other in the center and suspend the worm castings in the air. Run your hand down the material from top to bottom. This should push all the castings together to form a tight ball at the bottom. Twist the ball to contain the castings and tie it off.

This is essentially your worm castings tea bag.

You can skip this step if you don’t have any muslin cloth lying around. However, we recommend straining the worm castings BEFORE you use them in your watering can or container.

Worm castings tend to clog the spout and holes. Which is highly frustrating – believe us, we know from experience.

3. Steep The Worm Castings

Place your worm castings tea bag into your water and swirl it around to create movement in the water. This will help the water pass through your tea bag.

Leave your mixture to steep overnight while swishing it around occasionally. The more movement you create, the quicker the worm castings dissipate into the water.

You can also add molasses to the mixture to stimulate the beneficial microbial activity from the worm castings.

The molasses feeds the beneficial microbes and helps them to grow and multiply.

Adding molasses is entirely optional. We don’t go out of our way to include it in our worm tea. However, if we have it lying around in the pantry, we’ll add some to the mixture.

4. Worm Castings Tea

In the morning, your worm tea mixture should look a murky dark brown (like an over-steeped English breakfast tea).

Give the mixture one last stir before removing the worm castings tea bag.

Don’t throw your worm castings out! Unravel the muslin cloth and empty all that goodness onto your garden soil.

Congratulations! You’ve just made yourself some worm tea – your garden is going to love you for it!

If you choose not to encase your worm castings in a muslin cloth, you should strain the mixture through a fine wire mesh sieve.

Pour the mixture into a spray bottle or watering can and apply it to your next gardening project.

How to Make Worm Tea: Worm Tea Recipes for All Parts of the Garden

As we mentioned earlier, depending on the purpose of your worm tea, it is hard to provide the optimal recipe. Especially for more sensitive garden projects, like rearing seedlings.

This is why we’ve made it easier for you by detailing different recipes for different purposes.

Worm Casting Tea Recipe for Outdoor Gardens

When using worm tea on the established container or outdoor plants, you can provide a more concentrated form of worm castings tea. We also include molasses to stimulate the microorganisms (when we have it on hand).

The recipe we use is as follows:

  • 15 liters (4 gallons) bucket of water (unchlorinated)
  • 6 cups of fresh worm castings
  • Two generous tablespoons of molasses

We love worm castings and all their goods, but they are not a complete fertilizer solution. Therefore, if you have plants requiring specific nutrients and minerals, we recommend mixing them in commercial chemical fertilizer from your local nursery.

Worm Casting Tea Recipe for Seedlings

Feeding worm tea to seedlings

When working with seedlings, we always recommend diluting any fertilizer, including worm castings. Seedlings are sensitive and can easily experience fertilizer burn.

The proportions we use to make a weak worm castings tea are:

  • 4 liters (just over 1 gallon of water) of unchlorinated water
  • 1 cup of fresh worm castings

It is also good to note we prefer to bottom water our seedlings and allow the nutrients to soak up from the bottom. This ensures the delicate seedling leaves do not get burned if the fertilizer is too strong.

Frequently Asked Questions About Making Worm Tea

How do I Apply Worm Tea to My Plants?

We’ve described a few use cases for how to use worm tea in your garden throughout our guide above.

The easiest way to apply it to your plants is as a substitute for when you water them. After all, worm tea comprises mainly water.

You can use worm tea in foliar sprays, in watering cans, or use it when you bottom water plants.

How Long Can You Store Worm Tea?

We recommend using worm tea immediately after you finish making the mixture. That is the point at which it has the most nutritional value, and your plants will benefit the most.

The longer you leave worm tea, the less microbial activity, and beneficial bacteria.

At the most extreme, we do not recommend leaving worm casting tea for longer than a three-day shelf life. Shorter if it is warm weather.

How Frequently Should I Use Worm Tea on My Plants?

Because worm castings are considered a mild fertilizer (read about the disadvantages of worm castings HERE), you cannot overdose your plants with too much worm tea. This makes sense; otherwise, wild plants would suffer fertilizer burn if too many earthworms lived in their soil.

A good rule of thumb is to use worm tea 1-2 times per week, depending on the time of the year (less in colder months).

Is It Necessary to Aerate Worm Tea?

Aerating your worm tea during the production phase helps to stimulate the natural microorganisms living in the worm castings.

It has the same purpose as adding molasses to your mixture.

Therefore, if you are already adding molasses to your worm tea, aeration is not necessary.

That said, placing a fish tank bubbler into the water won’t hurt while you are steeping your worm tea bag. Not only will it aerate the mixture, but it will also help to move the water around to hasten the steeping process.