There were many questions about what orange oil was made of, where
you can buy it, how you mix the orange oil with the vinegar, and if it was
safe for people. Orange oil is extracted from citrus fruits. It is actually
extracted from the rind of oranges. The extracted liquid is composed of
mostly d-limonene, which is what gives an orange its aroma.
Orange oil is usually available at garden centers that carry organic products
and maybe some of the discount stores. The recipe for killing weeds is 2
ounces of orange oil to each gallon of the strongest vinegar you can find.
The stronger the vinegar, the faster the kill. The vinegar you have in your
kitchen cabinet is 5 percent, and pickling vinegar is usually 9 percent. There
is 20 and 21 percent vinegar available specifically for killing weeds. This
natural herbicide is safe to use around pets and humans.