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How to Turn Compost into Liquid Fertilizer
by Kerry Heafner - posted 09/25/15


How to Turn Compost into Liquid Fertilizer
Video Transcript

Today I'm going to show you how to take compost that you can generate at home and turn it into a liquid biologically active fertilizer that you can use in your home garden.

All you'll need to do this is:
• a bucket or other large container that will hold water

• aquarium pump and an air stone for an oxygen source for our soil microbes. And we'll put that down in the water and let it bubble. We'll also use the oxygen to help dechlorinate the water if you're using city water

• We'll put our compost in a mesh laundry bag which will function like a teabag. We'll measure our compost in a plastic measuring cup, and then we'll provide the soil microbes in the compost tea with a carbohydrate source. And for that, we'll use unsulfured molasses.

We'll start by scooping some of the compost we collected while ago into our laundry bag. Now this is a mesh laundry bag, but you can use whatever you have lying around the house – like an old T-shirt or a sock just any piece of cloth water can permeate through and soak the compost. And for this size of container, I'm going to use four or five good scoops. Some is going to fall through, but that's okay. Now I'm going to tie this up. This is going to act basically like a big teabag. Water will steep through this and over time discolor the water. The water will turn a tea colored brown.

Now the microbes in the compost will need an extra source of carbohydrates while the tea is brewing. For that we're going to use unsulfured molasses. We'll let this brew for 24 hours and we should have compost tea tomorrow morning.

Well it's been 24 hours since we started our batch of compost tea. Before I left yesterday I covered the barrel with some boards to keep all the bubbles, uh, on the inside. So, we'll remove these and see how we did. And I would say, judging from all the bubbles in here, looks like we did pretty well. All these bubbles indicate a lot of oxygen in here. So, that means our soil microbes are really active, and the population in here has increased exponentially.

Now, here's why we call this compost tea. As you can see the liquid is dark or tea colored. And at this point it's ready to use. And because it is a biologically active fertilizer, we have to use it right away.

You can use compost tea just about anywhere in the garden. Even on seedlings that are just getting started. At this critical stage in the plants life, the root system needs to have access to available nutrients, and the microflora in our compost tea will certainly help them. So, we're getting these seedlings off right with a healthy root system. That will mean a healthy plant later on. So, if you're looking for an affordable, easily obtained, organic fertilizer for your garden you can't do any better than compost tea.

For State-by-State Gardening, I'm Kerry Heafner.


Kerry D. Heafner is assistant extension agent in horticulture at the LSU AgCenter’s Ouachita Parish extension office in West Monroe. He is NE Region coordinator for the Louisiana Master Gardener program, and is an adjunct instructor of biology at Louisiana Delta Community College in Monroe.