Worm Tea- The Organic Gardener's Best Friend

By now everyone is familiar with the foliar fertilizer VF11. Foliar forms of liquid fertilizer containing nitrogen and other plant nutrients are sprayed on the plant and the soil around the plant. Worm tea provides many of the beneficial effects of VF11 at a fraction of its cost. In fact, except for the expense of the small amount of electricity used to operate an inexpensive aquarium air pump for a couple of days, there is no cost to homemade worm tea can be made for nothing. Controlled scientific experiments have shown that this miraculous organic foliar fertilizer increases plant growth and crop yields up to 50 percent. Of equal importance, if made correctly, worm tea contains billions, of beneficial microorganisms that cover the plant when the tea is applied as a foliar spray. These microbes prevent, or hinder the growth, of plant pathogens like powdery mildew, aphids, parasitic nematodes and spider mites because potential infection sights on the plant are occupied by the beneficial microorganisms in the tea. As a result, the pathogens cannot attach themselves to the plant. The harmful pathogens also have a difficult time establishing themselves on a plant sprayed with worm tea because the beneficial microbes consume the nutrients the pathogens require to grow and reproduce. Worm tea is easy to make. Basically, you need a three or four handfuls fresh worm castings, an once or two of a nutrient like sulfur free molasses or corn syrup and a way to aerate the brew. Some organic farmers add the juice of a lemon and an once or two of fish emulsion to the mixture. Aeration is a must when making worm tea to avoid the growth of anaerobic bacteria that may be harmful to plants. Aeration can be achieved with one of the inexpensive air aquarium pumps designed to oxygenate fish tanks. These devices, which cost less than $10 at a pet store, even have an air diffuser stone. You also will need a plastic bucket. I use a seven gallon food grade bucket sold at a local home brew supply store; however, the cheap 5 gallon buckets sold at Lowe's or Home Depot will work just as well. Finally, if you do not have a source of non chlorinated water, like rain or pond water, fill a bucket of chlorinated city water and let it sit for a couple of days to allow the chlorine in the water to evaporate. Alternately, add the chlorinated water from the tap to the brewing bucket and aerate it with the aquarium pump for a couple of hours to bubble out the chlorine before adding the worm castings and molasses to the bucket. Once most of the chlorine has been removed from the water, turn on the air pump and let the mixture ferment for 24 hours, 48 hours is better. I use a stick to stir the water in the bucket periodically but this is not necessary. After the brew is finished use a plastic funnel lined with a cloth towel to strain the tea before placing it into a garden pump sprayer. Worm tea will maintain its potency indefinitely if you continue to feed it and keep it aerated with the aquarium air pump. However, once removed from the brew bucket worm tea should be sprayed on the plants without delay since the beneficial organisms in the tea will not survive for more than a few hours if deprived of a continuous supply of oxygen. In this respect, the bottled worm tea sold commercially is of questionable value. Several commercial brands of worm tea have found their way to the market. The manufactures of these concoctions add preservatives such as phosphoric, lactic and citric acids to their worm teas. The acids supposedly put the tea's microbes into a dormant state. When the bottled teas are opened and exposed to oxygen, the microbes are said to recover. I do not know if the manufactures claims with respect to the effectiveness of their bottled worm teas are true or not. However, since worm tea is so easy to make, I question the wisdom of purchasing an expensive bottled tea that may be of questionable value. Why not just make the tea yourself and be done with it? There is no magic formula for applying worm tea to the plants in your garden. However, since the beneficial microorganisms in worm tea also are very sensitive to heat and sunlight, the spray should not be applied in the middle of a hot summer day. To be on the safe side, spray your plants early in the morning or in the evening after the sun has set. I spray every living thing in my organic garden, with the exception of my dog, with the tea at weekly intervals. Try it! I think you will be amazed at the effectiveness of this cheap effective organic fertilizer. For the sake of completeness, I should add that there are anaerobic as well as aerobic worm teas. Some authors even claim that worm teas produced under anaerobic conditions are superior to those created in an oxygen rich environment. Certainly, the microorganisms produced in an oxygen rich environment will differ significantly from those that thrive in an anaerobic environment. I believe that the preponderance of evidence suggests that anaerobic microorganisms may be toxic to plants; thus, I would avoid them.