We have talked of the toxic nature of lawn chemicals here on the Blue Heron Blog before, and we have cautioned against the use of Roundup (a non-specific weed killer). Today over on the Safelawns.org blog Paul Tukey is starting a three piece article on Roundup. Please visit and read, and then reconsider using this dangerous chemical.
Good Monday morning to you! To start the week off, I thought I might provide you with a serious topic to ponder, as well as a few beautiful images from a wonderful Garden Center.
Yesterday, we traveled to Greenwich, Connecticut and the beautiful Audubon Greenwich, for a private screening of the movie “A Chemical Reaction”. This powerful documentary, created by Paul Tukey And Safelawns.org tells the story of a the small town of Hudson, Ontario Canada, and their decision to ban the use of pesticides, and the movement that it began across Canada and hopefully the world. I have been anxiously awaiting the chance to see this movie, and had high hopes for the message it would deliver and the inspiration it might provide to millions of lawn loving Americans. I was not disappointed, and I believe as time goes on we will look back to this movie and remember how it started a change in our collective psyche of the way we view lawn care, and possibly even the lawn itself. If you are interested in a healthier environment for you and your family, want to learn of the toxic effect lawn chemicals pose, or simply like to hear a good David vs. Goliath story, you will enjoy this movie.
On our trip down to Greenwich, we made a side trip to Hollandia Nursery in Bethel, CT.
This wonderful retail nursery, boasts beautiful display gardens, a great selection of annuals, perennials, trees and shrubs, and further deepened my passion for retail garden centers. Enjoy these photos of their display gardens, and if you have the chance, I hope you will pay them a visit!
In Part I of our series on Compost Tea, we learned of the existence of the Soil Food Web. In Part II we learned about organisms within the Food Web, focusing on four building block organisms that plants use to gather the nutrients they need to survive. Now let’s take a look at actually brewing Compost Tea. First off, let’s start referring to Compost Tea in the correct manner, Actively Aerated Compost Tea (AACT). This distinction is important in order to differentiate it from other ways of applying organisms to your soil. The AACT process involves feeding and growing organisms under properly oxygenated conditions. If proper oxygen levels are not maintained, then some very bad visitors can show up in your brews. Hence the term “Actively Aerated”. Processes that simply steep compost without foods or aeration are ‘Leachates’ or ‘Extracts’.
Ok, so you have decided that brewing AACT sounds like a great idea, and you would like to try it. Excellent! Simplified, the process involves taking a high quality, well made compost, agitating the organisms from the compost into water, feeding and providing adequate aeration, and waiting for them to multiply. You will need the following materials to be successful;
Compost: Remember, in Part I we learned that not all compost is equal, and what some people consider compost, is not really compost at all. For our process, we are looking for a rich dark brown (think coffee grounds color) finished material, alive with organisms, free from pathogens and weed seeds. Finished meaning the compost has completed its process, and has sat long enough undisturbed for beneficial bacteria and fungi to grow to acceptable levels. If you do not have an adequate source on hand, compost for brewing tea can be purchased. It is important to obtain testing results for all compost, whether you have made it yourself or are purchasing it. All respectable companies selling compost for tea should be able to provide you with test results. Once purchased or made, your compost can be energized prior to brewing to give your fungi a head start. Fungi take longer to grow, so feeding them early (about 4 days with oats and Fish Hydrolysate) will give you a better chance of having them in your finished tea.
Water: You will need a chlorine free source, or if need be you will need to remove the chlorine. Chlorine being highly unstable, can be released from water by agitation for a period prior to brewing. Many municipalities are now using chloramines in drinking water, because it is more stable than Chlorine. This can not be agitated out, but can be negated simply buy adding organic matter to your water prior to brewing.
Brewing Container: AACT can be brewed in containers ranging from a five gallon pail up to large tanks holding thousands of gallons. You will applying your tea at a rate of about one half gallon per 1000 square feet of soil, so plan accordingly. Here is a great brewer, perfectly sized for the home brewer from Keep It Simple, Inc.
Source of Aeration: maintaining oxygen levels above 6 parts per million is essential in growing the aerobic organisms we are looking for. For small brewers, an aquarium pump can be used, while for large brewers, as we have (250 gallons), a regenerative blower will be necessary. A mesh bag: This is an optional item. The amount of compost used in relation to the amount of water is small, so it allows the brewer to use a mesh sack to contain the compost, making it easier to spray the tea, and simplifying the cleaning process. You may also choose to let the compost hang free in suspension, but you will need enough agitation from your aerator to help dislodge the organisms from the compost. Food for the Organisms: Depending on which organisms you will be trying to grow, you will use a combination of the following food sources; Fish Hydrolysate (NOT Emulsion!), Soluble Kelp, Humic Acid, Oatmeal (oats), and Organic Flour. It goes without saying that products should be all natural and/or Organic.
We purchase from the following, as we find the quality and service excellent with these vendors ; Neptune’s Harvest, Keep It Simple Inc., and Bob’s Red Mill. A Google search will produce companies in your area if these prove to distant form your location.
24 hours: What? Yes 24 hours, for that is the average time it takes for the organisms to consume all the foods and multiply into finished Actively Aerated Compost Tea. Now, if you’ve gotten this far and thought, WHOA!! this is getting to complicated, take a deep breath, making AACT is not as complicated as it sounds. If you find yourself still overwhelmed, take a look at these 2 products. They are pre-brewed AACT in a dormant state, with a shelf life of about one year, ready to be applied to your lawn or garden. They are ICT Organics 1-2-3 Compost Tea and Natures Solution Compost Tea. Both are produced by companies well versed in the production of Compost Tea, and both effective products.
For those of you still interested in brewing your own tea (and I hope there are a few of you left), tune in next time, for a discussion of the process and application methods. Thanks for hanging in through a long series!
In Part I of our series on Compost Tea, we had a brief discussion on the Soil Food Web and compost. We learned that these are tools we can use to restore the biology to our soils. Now would be a good time to talk about the microorganisms within the Soil Food Web, their roles, and then we can move on to brewing compost tea.
Healthy biologically active soil is home to billions and billions of microorganisms, and the four that represent building blocks for healthy soil are Bacteria, Fungi, Nematodes, and Protozoa. One teaspoon of healthy garden soil can contain up to a billion bacteria, yards of fungal hyphae, thousands of protozoa, and dozens of nematodes. Truly an incredible amount of life, all invisible to the naked eye, simply living and going about their daily routines. Let’s take a quick look at each group.
Bacteria are tiny, one-celled organisms and fall into four functional groups; Decomposers, Mutualists, Pathogens, and Lithotrophs. We are most concerned with Decomposers (which break down materials) and Mutualists (which form symbiotic relationships with plants), and want to avoid Pathogens (the bad guys) for obvious reasons.
Fungi are microscopic cells that grow as long threads or strands called hyphae, which push their way between soil particles, roots, and rocks. Fungi perform important services related to water dynamics, nutrient cycling, and disease suppression.
Nematodes are non-segmented worms typically 1/500 of an inch (50 µm) in diameter and 1/20 of an inch (1 mm) in length. Nematodes mineralize, or release nutrients in plant-available forms.
Protozoa are single-celled animals and are classified into three groups: Ciliates, Amoebae and Flagellates. Protozoa play an important role in mineralizing nutrients, making them available for use by plants and other soil organisms.
Bacteria and Fungi are the holder of nutrients, and nematodes and protozoa are the releasers of nutrients. In short, the nematodes and protozoa eat the bacteria and fungi, and poop out nutrient rich material. Always comes back around to manure, doesn’t it?
Growing and re-establishing these organisms in poor soils is essential to re-energizing the Soil Food Web. The numbers present and needed of each of these groups of organisms differs, depending on the existing soil ecosystem, and the type of crop one intends to grow. Perennial plant ecosystems (forest, tree and shrub landscapes and perennials) are generally fungal, while annual plant ecosystems (annuals and vegetables) are generally bacterial. Grass ecosystems (great plains, lawns and turf) tend to be slightly bacterial. These compositions are important to note whether making compost, steeping Leachate or brewing Compost Tea. By building the correct soil organism communities, we provide plants an environment they can easily exploit, giving them the best opportunity to thrive. This is the essence of the organic process.
You may be asking, “How can a plant exploit?” Great question. Plants actually attract beneficial microorganisms. Say what? That’s right, plants, by releasing nutrients called exudates through their root walls into the rhizosphere (an area of only a couple of millimeters wide surrounding the root), attract the organisms they need to survive. The exudates attract bacteria and fungi that will in turn supply the plant with the nutrients it needs. Pretty cool eh? The plant actually attracts and feeds the certain bacteria and fungi that produce, or help the plant find the nutrients it needs to survive. It’s gardening on a microscopic level.
You now have a very basic understanding of the Soil Food Web. As with any complex subject, it can not adequately be covered in short blog posts. I will be providing you with suggested reading material and reference links at the end of the series.
Compost Tea or Actively Aerated Compost Tea (AACT) as it should be known, is gaining popularity amongst organic practitioners and home gardeners, but finds itself in the midst of controversy over its efficacy. It’s time to take a closer look at this very effective tool in the organic arsenal.
Any discussion of compost, AACT, and organic gardening, should begin with The Soil Food Web. Similar to the food pyramid used for nutritional guidelines for humans, the Soil Food Web is a mapping of the life and interaction of the organisms in healthy biologically active soil. Here organisms eat, live and excrete, and in turn are eaten and excreted by other organisms, producing nutrients for other organisms in the Foodweb and for the plants growing amongst them. So what keeps the Foodweb cycling? Compost. Compost, as most everyone knows, is produced by the decay or breaking down of organic matter by microscopic organisms. It is the foundation of Organic Gardening. Everything necessary for a plant to survive can be found in well made compost. At the basal level, composting really is the process of growing the microorganisms of the Soil Food Web, and organic gardening is the process of reintroducing these organisms back into the soil of our gardens. All compost, however, should not be considered equal. Nature has created very specific regenerative cycles for each of its plant communities, and by following these examples we can effectively create and maintain healthy, biologically diverse soils. I’ll have more on that in upcoming posts.
Ok, so up until now, whether you’ve knew of the Soil Food Web or not, if you use compost to amend your planting beds or topdress your soils, you have been growing and applying the microorganisms necessary to promote plant health. Bravo! You are doing your part to help nature succeed, contributing to the health of our planet and reducing our dependency on chemicals. There is an easier way however, and it’s here that Actively Aerated Compost Tea (AACT) can be a very effective and efficient tool for you.
It’s important to note here, the different techniques using compost and water to apply nutrients to the soil. They are; Compost Leachate, Liquid Compost Extract (LCE), and AACT. To produce Compost Leachate, one simply adds compost to water and lets it sit for a period of time. The resulting liquid is then strained and applied to one’s soils. To produce LCE, one uses the same process as Leachate, but agitates the slurry, either by creating a vortex or aerating (bubbling) the solution to extract the microorganisms and nutrients from the compost. The resulting liquid is then strained and applied.
The process of making Actively Aerated Compost Tea (AACT) uses a small amount of compost in water, and blasts the microorganisms (through aeration) from the organic matter. Foods are then added to the tank, and consumed by the microorganisms. This is the beauty of AACT. When brewed with well made compost, the correct amount of foods and adequate levels of dissolved oxygen, the microorganisms multiply exponentially, and safely, producing a solution rich in microbial activity, that when applied, infuses the soil with the biology necessary to sustain plant life.
In part II, we’ll discuss the some of the organisms of the Soil Food Web, and the process of growing them by brewing AACT.