Recipe #56 Stinging Nettle spray Categories: Garden, Disease, How to make Stinging Nettle Spray. We have talked in the past about it being planted with some plants to enhance oils such as herbs. Here is another thing Rodales recommends: It helps plants resist infections by many fungal diseases. On a plant that has a mild case of Botrytis rot or powdery mildew, pick off infected areas then spray with this solution to help to resist further infections. During long, cool, wet periods you can also use it to strengthen plants. Made into a tea (Stinging Nettle Tea) it repels aphids and give plants a good dose of trace elements. Gather 1 lb. of leaves of stinging nettle (Urtica dioica). Crush, put into a burlap bag or old pillowcase. Submerge into 1 gallon unchlorinated water. Cover bucket, place in warm area, let it sit for 1 wk. When you open bucket, smell will be strong. Strain through cheesecloth. Store any extra in glass containers but don't keep longer than 1 month. Mark jar by date you store or expiration date. How you use it: You dilute the concentrate by adding 5 parts unchlorinated water to 1 part of the concentrate. Depending on the seriousness of disease, spray every 2 wks to once a month. Of course remember the note above at certain times it can be used to strengthen plants as well... Info from Rodales. -----