Why you need compost Tea and how to Make it

Why you need compost Tea and how to Make it


Compost Tea is a safe, easy way to increase the vitality of your plants while reinforcing a healthy microbial population in the rhizosphere. While compost has historically been a fantastic source of food and beneficial microbes when incorporated into a traditional soil garden, utilizing the tea brewing method allows for the same benefits across a wider spectrum of plant growing techniques. Hydro gardeners, if you want to ensure you have a bountiful, great tasting harvest, consider adding tea to your weekly regiment.

Compost tea can be applied to the plants as either a root drench, foliar spray, or both! Additionally, the solution is suitable for either soil or hydroponic applications. So now you’re probably wondering “How do I get me some?!” Well, there are a couple of ways. If you’re low on time and want to skip the process of making compost tea, stop by your local specialty gardening store and pick some up freshly brewed or pre-bottled

 Here at Taproot Hydroponics, we brew a fresh, proprietary tea blend on a weekly basis for our walk-in customers. Because we service such a wide group of garden enthusiasts we have opted for a custom mix that can be used in any phase of plant development, but really shines during the fruiting stages of fast blooming annuals. First, we treat our water using a HydroLogic® Small Boy filter. Chlorine and chloramines will kill the microbes in your tea, so will any added h2o2 in a hydroponic reservoir. The Small Boy filter allows us to use our water fresh without waiting for the chlorine to gas off. It also helps ensure a clean slate for our tea by removing heavy minerals and metals from the water.

A healthy tea is a living thing requiring a few things to get going; a vessel or container to hold the water, compost (of course) and air being the primary ingredients. Just as your plants require oxygen to thrive, the living cultures in your tea require an oxygenated state to thrive. If you are making a tea with a focus on microbial populations, you will want to include a few things such as garden soil, earthworm castings, or even pre-prepared microbe inoculants. A food source such as molasses or any other simple sugar should be added a few days after inoculants are added and within 48 hours of use to prevent an issue with overpopulations.


The other way to obtain this highly enriching form of plant nourishment is to make your own. We’ll walk you through making a basic compost tea and afterward we’ll discuss how to use this compost tea.


A healthy compost solution can be created in a number of ways. From a simple bucket and strainer all the way to actively aerated vortex mixers that look like something out of a sci-fi movie or Breaking Bad. Here we will be looking at a cheap, easy way to get in the tea game.


Things You’ll Need

  1. 5-gallon bucket.
  2. Air pump and stone.
  3. Compost.
  4. Strainer.
  5. Molasses.


  1. First, you will want to start with clean, dechlorinated water, or if using tap water you can let your air pump run in the water for 24 hours to remove any chlorine.
  2. Next, you will add your compost. You can either put this directly into the water (though it will be messy) or put it into an old sock or nylon to help contain some of the mess. A good starting point for the first time brewer is 2-4 cups of rich compost per 5 gallons of water.


You will want to let this mix brew with the air pump running for 24-48 hours to extract as many beneficial elements as possible.

  1. If possible, add a tablespoon of molasses 12-24 hours before use to really help the microbial populations explode into action!
  2. Be sure to use or refrigerate any tea before it ‘expires’. The active lifespan of your teas may vary considerably, but 1-2 days after adding any molasses is a good rule of thumb.


The one thing any good compost brewer needs…is compost! This can be created at home or purchased at your local specialty garden shop for convenience. If you are making your own compost, you may have the ability to ‘custom tailor’ a compost blend to complement specific plants or plant life cycle phases for your garden. If you are limited on space, however, you may be better off using a ready-made compost as the manufacturers generally sort their ingredients for consistency and to ensure an ideal ratio of carbon and nitrogen producing materials.


Other materials can be added to these living teas such as guano, sea kelp, molasses, fungal & bacterial cultures and even certain fertilizers (along with much, much more). With such customization available the gardener can and should be creative, however, it is important to not overload a brew without a clear understanding of microbial population and how to monitor it lest the solution spoil. Teas can go bad from age or an imbalance of fungal/bacterial cultures in relation to their food and air supply.


Put short, an overabundance of these cultures strip the solution of the very elements they need to survive while continuing to multiply leading to eventual starvation.

To best avoid this, solutions should be brewed and used as fresh as possible with any leftovers refrigerated and storage kept to a max of 2-4 days under ideal conditions from the time the tea leaves the brewer. 


For Hydro

Hydro gardeners may benefit from applying the solution directly to the plant sites, though the tea can also be added to your reservoirs a few days before changing them.


Make sure to monitor your reservoir temperatures and keep them from overheating. A nice cool solution between 60 and 65 degrees is ideal. Growers maintaining a sterile system or using H2o2 for root oxygen will be faced with a dilemma, as mentioned above the living cultures will be neutralized (killed off) by the H2o2. This may be a fine place for a foliar application though. Be creative! Some growers have found an active living root system to be more resilient to issues like pests and pathogens with the added benefit of a living ‘soil’ web ensuring maximum water and nutrient uptake.


From simple to complex gardeners will surely see the benefits of incorporating a tea into their regiment.

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