Willow extract is used as an organic rooting stimulator or growth booster, encouraging plant roots to grow stronger and faster in any type of gardening set-up.
Willow extract contains two auxins – salicylic acid and indolebutyric acid – and is obtained from the growing tips of willow branches.
When it comes to rooting cuttings from mother plants, most growers like to add rooting hormones before planting to encourage the cuttings to take root. Among their options are synthetic rooting hormones in the forms of liquid, powders, or gels; however, an organic option is willow extract.
Cuttings are propagated in many different types of gardening, ranging from in-ground garden beds and herb gardens to indoor gardens (hydroponic/aeroponic set-ups). In all of these situations, a solution needs to be found to encourage cuttings to root faster, and to resist disease. Willow extract can be used for exactly that purpose.
Willow extract is little more than a solution of water and two auxins, or plant growth hormones. Namely, these are salicylic acid and indolebutyric acid. They’re found in very high concentrations in the growing tips of willow trees. Combined, these two auxins trigger exponential root growth in cuttings, while also providing them with protection from disease, mold and fungus.
While willow extract is available in commercial formats, you can make your own if you have access to a willow tree. A mason jar (with lid), a few cuttings from the willow’s growing tips, and a couple of cups of water is all you’ll need. Combine the water and willow tips in the mason jar, seal the jar and let it sit in the sunlight for a few days.
The water will turn from clear to a light yellow in color. When this happens, you can add the willow extract to your cuttings. Note that making your own extract can be done all year long, although auxin levels are highest during spring’s heavy growth period. You can also use cuttings from any member of the willow family – it does not need to be from an actual weeping willow.
Other organic options for rooting hormones, as an alternative to willow extracts, are sprouted seed teas and regular honey.