Can You Use Dried Willow Bark to Make Rooting Hormone?

Trees for Willow Tea

• It doesn’t make any difference what species of tree or shrub in the willow genus Salix that you use. There are some 400 willow species and shrubs with varying climate requirements, but the commonly grown pussy willow (Salix caprea) will grow in U.S. Department of Agriculture plant hardiness zones 4 through 8 and the graceful weeping willow (Salix babylonica) will grow in USDA zones 6 through 8.

Brewing the Tea

• Collect about 2 cups of pencil-thin willow branches about 1 inch long. These should be young, first-year twigs with green or yellow bark, not gray or brown bark. The IPA you’re after is in the sap, which is why dried bark won't work. Pour boiling water on the twigs and let them soak overnight or soak them in tap water for several days. Strain out the twigs and there you have your rooting solution.

Rx in the Tea

• Look on an aspirin label and you’ll see that the active ingredient is acetylsalicylic acid. Willow sap contains salicylic acid, a closely related chemical. Bacterial, fungal and viral infections are among the largest threats to cuttings establishing new roots. Salicylic acid leaching into willow tea along with IPA helps newly propagated cuttings acquire SAR (Systemic Acquired Resistence) to fight plant disease. This make willow tea a dual-purpose rooting solution.

Using Willow Tea

• Soak the cuttings you want to root overnight in willow tea or pour it directly on the soil where you have cuttings that you want to root. Moisten the soil around the cuttings several times as they grow roots. If you keep a tight-fitting lid on the jar, your rooting solution will remain useful for up to two months.