Horsetail Fungicide recipe (taken from
http://littlegreenblog.com/)
In a large glass or stainless steel pot, mix 1/8 cup of dried horsetail leaves in 4 1/2 litres of unchlorinated water (use water from your waterbut or let some tap water stand for a couple of days)
Bring to a boil, and simmer for 1/2 hr.
Cool, strain, bottle and label. The infusion will keep for a month which is long enough for you to keep reapplying to your crop. Any left overs can be used as a wonderful hair rinse.
To use, dilute the 1 part horsetail concentrate to 5-10 parts unchlorinated water. Spray infected plants once every week or two in dry weather or daily if it is raining. Can also be used as a preventative measure if there is a threat of blight in your area.