Compost

Aerated Compost Tea Simplified

Be sure to watch the video in this article!

Compost Tea

Compost tea is great for keeping your plants fed and healthy throughout their life. It’s not like strong chemical fertilizers that can burn your plants if applied heavily. Additionally, if the brewing process is done correctly, compost tea is not toxic like chemical fertilizers either. What could make it toxic is the introduction of compost that has not properly cooked. According to Bradley, F.M., Ellis, B.W. & Phillips, E. (2009), “E. coli can be present in the raw ingredients of a compost pile.” (p. 162). When gathering the compost for the tea, one must ensure that the compost is suitably finished. The best way to determine if the compost is suitable for use is if it has a sweet earthy aroma.

When the tea is brewing, nutrients and beneficial bacteria are extracted from the compost. If the tea is laced with something sugary, molasses for example, the bacteria will feed and multiply making the tea even stronger. These bacteria and nutrients are suspended in the water and made more easily available to the plants. As an aside, compost tea can restrain fungal plant diseases.

No Heat Required

Although the composting process requires temperatures from 135 to 155 degrees, compost tea is not boiled or cooked. There are two brewing variations that work well. The first is letting the compost set in a barrel or large bucket of water, and stirring it daily for about a week. The second way, and the way we will discuss here is by aerating the tea for 24 to 36 hours. In the event that you want to go off grid or the world has come to an end as we know it, then the week long process will probably be the only choice available if the power grid no longer functions. Of course, this will be discussed in a future article.

The following process is definitely not set in stone but has worked well for this author. As you begin making your own compost tea, feel free to experiment with the process. You never know, you may come up with something that works better for you in your situation.

The process and the materials

One of the most convenient and least expensive containers to use for brewing your compost tea in is the ever popular 5 gallon plastic bucket. I don’t know about you but I probably have 20 or so of those things hanging around waiting to be used. They are pretty easy to find at The Home Depot or Lowes. Just use your imagination and you should be able to come up with something that will work.

The water

5 gallons of compost tea is a good number to start with but of course that depends on the size of the garden you plan to feed. I have around 60 square feet of garden that I water and I mix the finished compost tea with dechlorinated water at a 1 to 1 ratio. In reality I don’t get a full 5 gallons because I don’t fill the bucket to the rim. I’ll usually get about 4 and ½ gallons making me 9 gallons after mixing the water and compost tea.

Now, if you have rain water, spring water, or some kind of water that has not been processed through your municipal water treatment facility you should be good to go. However, if you want to use city tap water and you don’t have a good carbon filter or some way of removing the chlorine, you will need to let the water gas off. There are two ways that I use to do this. One way is to fill your bucket with the tap water and then just let it set for 2 to 4 days. If the water is treated with chlorine, this should work just fine. The chlorine will evaporate.

If the water is treated with chloramine, there is a lot more that goes into getting rid of or reducing chloramine in tap water. Much more than the scope of this article covers. The best advice is to contact your municipal water treatment facility and find out if they use chlorine or chloramine. If they use chloramine ask them how you can remove it. If they use chlorine, then standard gassing off methods should work fine.

The other process for removing chlorine from your tap water is to put the water in a 5 gallon bucket and run air lines from an aquarium pump into the bucket. You should aerate the water for about 3 hours and this should gas off the chlorine. Once the water is dechlorinated, you are ready to introduce the compost and start the brewing process.

A few Words About Aquarium Air Pumps

If you don’t already have an aquarium air pump, they are not hard to find and fairly inexpensive. For example, I bought mine (a Top Fin 4000) at Pet Smart for around $19.00. It’s designed for an 80 gallon tank, has two air outlets, and an adjustment wheel to adjust the air flow. When brewing tea and off gassing chlorine I just leave it cranked all the way up. Amazon has something similar for $16.00 to $21.00. It is the JW Pet Company Fusion Air Pump 700 Aquarium Pump. The main thing you want to be sure of is that you have two air lines going into the water and/or compost tea.

Additionally, at the end of the two air lines you will need air stones. You want to find air stones with very fine air holes however, whatever you can afford will still work well. Air stones are not that expensive anyway. My favorite air stones have been the Top Fin large Round Airstones. They’re about the size of golf balls and spread the air bubbles nicely. They will stay at the bottom of the bucket without the need to weight them down as well.

Putting It All Together

When your water is ready, you can start adding the ingredients to start the compost tea brewing process. Find yourself a 1 gallon paint strainer bag and fill it about halfway with compost. Covering all aspects of compost and the science behind it is way beyond the scope of this article. I won’t go in depth about compost but will say that if you have some good mature compost that is moist and smells good, it should serve you well. I will probably cover compost more in depth in a future article so stay tuned for that.

Get a stick, a piece of pipe, or something that will lie across the top of the bucket and hold the weight of the compost tea bag. Without damaging the tea bag, secure it to the center of the stick. If you do not damage the bag it can be cleaned and reused several times. After securing the bag to the stick, lay it across the top of the bucket so the compost submerges in the water. Situate one of the air stones directly under the tea bag so the air bubbles will keep the compost agitated. Situate the other air stone as far away from the first in order to distribute the air bubbles as evenly as possible.

At this point you are brewing compost tea and if you let it brew for about 36 hours you would have a decent batch. However, there are a couple of other things we can add to enhance the tea and make it even stronger. I’ll talk about two of those ingredients here.

Feed The Beneficial Bacteria

The more important of the other two ingredients is some unsulfured molasses. You can pick this up in any grocery store and the keyword here is “unsulfured.” Pour about 2 ounces of the molasses into your bucket. Molasses is sweet and will feed the beneficial bacteria in the compost which will cause it to multiply. I can’t prove it, but I have heard that the bacteria will double every 7 minutes. That’s a lot of beneficial bacteria after a 24 hour period. So, if you use molasses decrease the brew time to 24 hours.

Maxi Crop Liquid Seaweed

The second additional ingredient that I like to use is Maxi Crop Liquid Seaweed. Derived from Kelp, Maxi Crop Liquid Seaweed contains over 70 minerals, micronutrients, amino acids, and vitamins. It helps with root development and promotes tolerance to plant stresses. It can be alarming when first applied because nitrogen will be sapped out of the soil to help break the seaweed down and this can cause yellowing of some leaves. However, when that process is finished the resulting plant health is well worth it. The bottle will have a cap that can be used to measure the liquid seaweed into the tea. Use one cap full to every gallon of tea. If you can’t find Maxi Crop Liquid Seaweed locally head on over to amazon and you should be able to find it there.

Conclusion

It is the opinion of this author that after an “SHTF” situation, compost tea is going to be one of the few choices survivors will have for fertilizing their crops if not the only choice. The compost tea brewing process by aeration discussed in this article may or may not be available. It depends on the availability of electricity in order to run the air pump. In the event that electricity is not available, the gardener will be left with the 5 day steeping process. Until that happens, you can use the aeration process which is quicker and provides the opportunity to learn about compost tea and its benefits.

References

Bradley, F.M., Ellis, B.W, & Phillips, E. (Eds.). (2009). Ultimate Encyclopedia of Organic Gardening (Newly Revised And Updated). New York, NY: Rodale’s.