compost tea for gardening

Let’s Have a Compost Tea Party!

Imagine their amazement as your gardening friends enter your yard. Surprised by the lushness of your plants. Stopping to admire the size and quantity of the beautiful blooms in the flower beds. Taking in the abundance of your vegetable garden. One friend finally asks "What are you doing? Your garden has never looked this wonderful."

You smile and reply, "I’ve been having compost tea parties with my plants."

What’s So Special About Compost Tea?

Sometimes compost tea is confused with compost extract. But here are major differences between the two. A compost extract is made using only compost. It’s beneficial for your soil, especially as a drench, but it doesn’t contain the extra food found in compost tea. Recipes for compost tea always contain sources of food to promote for additional beneficial microorganisms.

Compost tea benefits your plants, and soil, as an overall health stimulant. It can be used as a foliar spray on plants and as a soil drench. When used as a foliar spray it protects your plant leaves from many fungal and bacterial pathogens. There’s only so much surface area on a leaf and if it’s taken up by the beneficial microorganisms in the compost tea there’s no place for pathogens.

As a soil drench it feeds the plants and the soil. The microorganisms in the compost tea soak into the mulch and leaf litter to begin decomposing organic matter. Using compost tea adds microorganisms to your soil and adds soluble nutrients from the compost it was made from. Those nutrients give the microbes something to eat.

How Is Compost Tea Made?

Compost tea is made by submerging a mesh bag filled with compost and other ingredients into a container of water. The water should stay constantly aerated to maintain good levels of oxygenation through the process. The mesh bag should be placed in such a way that its content is agitated by the constant airflow. The force of the airflow applies gentle force to extract the beneficial microorganisms, along with some soluble nutrients. Compost tea contains all the organisms that were in the compost before brewing as well as additional microorganisms from other ingredients. It’s important to maintain proper aeration to maintain constant aerobic conditions.

What Are The Steps For Making Compost Tea?

There are only a few steps. This is an easy way to add nutrients to your garden.

Compost tea is only as good as the compost you start with. It’s critical you source compost - animal, plant, or a mixture - from a reliable source. It has to be compost that is completely decomposed; you shouldn’t be able to recognize any bits of food or animal manure. Give it the sniff test, it should smell like fresh soil.

Compost has to be free of chemicals that are used to kill fungi or bacteria. You’re trying to create greater colonies of microorganisms and using a base that kills them is counterproductive.

The best source is making your own!

The Steps To Microbe Rich Compost Tea

1. Gather your supplies

  • 5-gallon plastic bucket
  • Fish tank aerator (around 3.0 psi)
  • tubbing
  • Compost tea brewing bag (We’ll get into that later)
  • Big handful of completed compost
  • Additional foods for the microbiology you wish to increase. Kaytonik is a great source of fungal food; other types of catalyst that can be used are fish emulsion, or seaweed extract. Adding Mycorrhizal fungi will also benefit your plants.
  • Hydrogen peroxide for clean-up

2. If your water is chlorinated, let it set for 24 hours before you start brewing your compost tea

3. Mesh bag for the solids

  • Can be from many sources but has to have pretty small holes – hole size should not be larger than 400 micrometers.

Now The Fun Begins

Compost tea is only as good as the compost it comes from. Garbage-in garbage-out or, in this case microbes-in, microbes-out. If your source is low in microbes (bagged compost from the store) you’ll have to add microbes to get a good quality compost tea. That’s where Kaytonik becomes very beneficial for your compost tea. It’s high in humic and fulvic acids and also stimulate microorganisms activity. (You can also learn about why humic and fulvic acids are important.)

You have all your supplies, including your compost. Secure the air tubes at the bottom of the bucket making sure that they won't move once the air starts pumping. Your 5-gal bucket should be ¾ full to limit any over spillage from the bubbles created by your aeration system. In the mesh bag place the compost. Add ½ a cup of the Kaytonik directly to the water.

Your water temperature should be at ambient temperature to reduce any thermal shocked when adding the compost in the water.

Where To Put Your Compost Tea While It’s Brewing

I put my 5-gallon bucket with all the ingredients just inside the back door on a boot tray.

The proteins in the compost have a tendency to foam, so the boot tray takes up any spillage.

Placing a bubbling bucket of compost and water by the back door may be controversial to your family. This may involve a family discussion. These are the points you want everyone to understand

  • It’s only for a day
  • It can’t be out in the sun, UV rays kill off bacteria
  • Aerated compost tea does not smell bad, if it does smell bad it’s going anaerobic and you’re going to take it outside immediately
  • For best results, the water has to be 68º – 72º F (20º -22º C)
  • You’re doing this so they can eat more nutritious vegetables and the flower gardens will be more beautiful

It’s Ready – How To Apply Compost Tea

Use it the very next day. As soon as you unplug the aerator, you’re losing oxygen in your water and your tea will go anaerobic. Take your bucket outside and pull the compost mesh bag out and set it aside in a pail. If you’re intending to use a spray tank, you’ll have to filter your compost tea. If you’re planning on hand watering, you don’t need to filter your finished product. For foliar spraying dilute the compost tea 1:4 or 1:6 with water and cover the leaf surfaces thoroughly.

Filtering removes any solids that may clog a sprayer but it also removes microorganisms clinging to that tiny solid. So, after spraying be sure to wash everything thoroughly, preferably on the edge of the flower bed or vegetable garden. Why waste good microorganisms? There are lots of microorganisms still in the nooks and crannies of your equipment.

You also need to clean everything thoroughly because undesirable bacteria may decide your equipment is a hospitable environment. Blow out the aquarium equipment with dilute hydrogen peroxide solution until it runs clear. Scrub your bucket with a diluted hydrogen peroxide solution to take care of any unwanted bacteria.

You now have a lovely gob of compost. Turn the tea bag inside out and deposit it where it appears your plants need more nutrients. That isn’t even enough to really be called compost, but your plants will love it. Spray down the bag and swish in the hydrogen peroxide water. Dry it and it’s good for another batch.

Now, put everything away and wait a couple of weeks. You should see signs that your compost tea is beginning to work.

  • Less insect problems
  • Fewer disease issues
  • Less watering needed
  • Leaves greener and lusher
  • Flower plants with more blooms; vegetable plants with more fruit

Your family won’t need to be convinced again. They’ll see the results, just as your gardening friends did. Now they know you’re the expert when it comes to compost tea.

Will You Be Preparing A Presentation On Compost Tea For Your Gardening Friends?

As your gardening friends leave and walk past your garden, they again ooh and ahh at how healthy your garden is. Everyone wants to know how they can give their gardens a boost.

You tidy up your kitchen after your guests have left. Moving the scraps to your compost bin. Coffee grounds, tea bags, and vegetable and fruit scraps will live another life as the base for another batch of compost tea.

Want to know more about how the microorganisms in your soil benefit your plants? Find out by checking our recent blogs.

Posted in: Soil For Humanity

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