Special Topics in Horticulture: Organic Landcare

Student Blog Post by Jay Holder & Cecelia Lamberty

As the agricultural world has progressed into mass production of food through malpractice, degrading soil’s structures, quality and the loss of valuable microbial ecosystems, humans have become blind to the big picture. To raise happy, thriving plants you need healthy soil, to have healthy soil you need a healthy soil ecosystem. This ensures the ability to be able to sustain our dietary regimes for the foreseeable future. Over the past three weeks Christina Nikolic, a SOUL Certified Organic Professional and instructor, has been teaching us the better, sustainable methods of Organic Landcare; how to regenerate healthy soils from depleted resources, to think of ecology and to care about the health of our gardens as a whole. 

The goal of Organic Landcare is a practice that maintains holistic health of the garden through the use of non-toxic substances derived from plants, animals, or carbon based derivatives. If you are interested in transitioning to or starting your own organic garden, Christina recommends this 3 step process: build the foundation, use organic broad spectrum fertilizers, then use organic nutrient specific fertilizers. Taking the first step in that 3 part process is about changing the way we think about soil. Too often we place too much emphasis on what we are growing in the soil and not on growing the soil itself. Building healthy soil starts with mulch. The main function of mulch is to act as a source of organic matter that will be broken down over time and add nutrients to the soil. Protection from the forces of nature such as compaction from rain, drying out in the sun and losing the ability to retain water are other important roles mulch plays. Providing a source of food for beneficial microorganisms is the foundation of creating a balanced-soil ecosystem. Once you mulch, the microorganisms will make their way there naturally.

If patience is not your strong suit, you can speed the process up by adding them manually with a liquid culture. ‘EM’ trademark (short for effective microorganisms) was developed in the 1980’s in Japan by professor Teruo Higa. The mother culture consists of 17 different species of bacteria, yeasts and fungi. To make a daughter culture, you combine 1 part organic, unsulfured blackstrap molasses to 1 part mother culture to 20 parts water ( if using tap water add 1 tablespoon of humic acid). Allow this mixture to ferment over the next few weeks, releasing the gas build up every few days. When it has finished and is ready to use it should have a pH between 2.9-3.8. Various dilution rates are needed depending on its purpose. For use on soil or compost, dilute to 2 teaspoons per litre or 1-100 ppm. Adding this bio stimulator to soil jump starts microbial activity which in turn attracts other beneficial insects such as nematodes, millipedes and earthworms. Once introduced to the soil it is important to keep up proper moisture levels, however seeing as mulch should’ve been applied, water evaporation becomes less of a problem.

The next step in the process involves using organic broad spectrum fertilizers such as compost tea, kelp extract and insect frass. These fertilizers all contain nitrogen, phosphorus and potassium in almost equal ratios along with other micronutrients that help boost the plants along during the growing season. If your plants are still showing signs of nutrient deficiency, then it is time to get a soil test done and go to step three.

Step three is figuring out the organic nutrient specific fertilizer you will need based on the soil testing. A proper soil test will also tell you the pH of your soil. Often if your pH is in an unfavorable range and you correct it, a lot of the issues will be corrected naturally. The ideal pH for all purpose gardening needs is between 6 and 7, which is considered slightly acidic to neutral. If the test shows low: phosphorus, add rock phosphate or bone meal, magnesium, add Epsom salt or lime, potassium, add wood ash, calcium, add lime, oyster or egg shells, nitrogen, add blood meal etc. These fertilizers can upset the ratios in the soil though, so it is better to use these specific fertilizers in small amounts over an extended period of time.

Changing the way we look at weeds can also be super helpful in determining soil health. Instead of looking at weeds as a nuisance or a problem, try viewing them as indicators of deficiencies or an overabundance of nutrients in the soil. Weeds can tell you a great deal about what is going on in the soil just by which ones are present or persist. An example of this is the common dandelion (Taraxacum officinale) which can be a sign of low Ca, P, vitamin A, humus and Fe, or can also indicate high levels of K, and Cl. Their presence can also tell you that there is poor residue decomposition and good drainage. This can be very useful information when determining what specific amendments are needed. Looking at weeds in a different perspective can be very insightful but they are not the only clues the soil is giving. Insect infestation is another tell plants give us. Weak plants, nutrient availability or lack thereof and soil compaction are all reasons insects may choose to go after certain plants and should not always be the signal to run for the pesticides. Sometimes an infestation can lead to a beneficial predator showing up to lay its eggs leading to a better balance in the soil. Looking at some of these issues in a different way often leads us to an organic, holistic solution.

Through the combination of no tillage or use of chemical fertilizers and pesticides, and the use of mulch, effective microorganisms, moisture and organic products; we are creating healthy soil full of happy microorganisms and hyphae networks, which has quality structure and good nutrient/water retention that provides the plant with everything it needs to fend for itself, making it less susceptible to disease. By following Christina’s steps: starting with the building of a foundation through mulch, microorganisms and moisture, then using an organic broad spectrum fertilizer, or further progressing to a nutrient specific fertilizer, we are creating a healthy sustainable environment for our garden to thrive as a whole for many years to come.

Image: https://www.yesmagazine.org/environment/2018/10/05/call-for-submissions-the-soil-issue, May 19, 2021