Defer Fungus from Plants Using Horsetail or “Equisetum” (Biodynamic Field Spray) by Karin Bellemare
Horsetail can be found all over the world. The Horsetail that is commonly used in Biodynamic farming is field horsetail or “equisetum arvense.” The plant contains silica, potassium, and calcium. All of these properties make it an excellent treatment for fungus in the garden. Fungus is most prevalent during high humidity and long spells of rain. The silica in the horsetail eliminates large amounts of water around the plants making it difficult to spread fungus. To prevent fungus follow this recipe below.
Recipe for Horsetail or “equisetum” spray #508 in biodynamics.
Ingredients/Tools
1 Unit Horsetail Herb (can find at Josephine Porter Institute online)
1 Quart water + 4 Gallons
1 Pot with lid
1 Garbage Can/Bucket that can hold 4+ gallons
Backpack sprayer (preferably used for biodynamics only)
1-2 hours time
First, combine in a pot, 1 unit horsetail and 1 quart water. Place the pot on stove, cover with a lid and turn heat to low. “Cook” the mixture for 20 minutes. Next, remove pot from the stove. Fill garbage can with 4 gallons of water. Add the mixture from the pot into the garbage can. This dilutes the mixture to the right consistency for the garden.
Now, set a timer for 15 minutes. It is now time to create a vortex and mix. Using one arm stir the water into a vortex. Once it has reached a vortex switch directions and create another vortex. Repeat for 15 minutes. When the stirring is complete strain contents into the backpack sprayer.
Now its time to apply our #508 spray to the garden. Target plants that are most susceptible to fungus (tomatoes, squash, swiss chard, potatoes, to name a few) If there are affected areas of the plants make sure indefinitely to spray those areas! Cover the entire plant as a preventative and to eliminate fungal growing conditions.
1 Unit will cover 1-acre of land. (Adjust quantity as needed) This can be applied daily during outbreaks of fungus. Otherwise, apply every 5-7 days.
Enjoy! And always remember to rest your arm after 15 minutes of stirring!








