Willow water is a traditional method to extract the rooting hormone indolebutyric acid from willow (Salix) trees, which is believed to be present in sufficient quantities to stimulate root growth.
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Referencesedit
^Ohio State University Extension, "Gardening Folklore".
^Tips On How To Make Willow Water Gardening Know How
^Using Willow Water to root Rose cuttings Texas Rose Rustlers. Pamela Ashworth Puryear. 1986