One of the nice things about growing willow trees is how easily and fast they grow. You can plant a 2-foot seedling and within a couple of years, it will be over 15 feet high. One of the best ways to propagate a willow is by taking cuttings of an existing tree and rooting it. Within a few months, you will have a new willow tree. Rooting is simply a process of several steps that stimulates the tree into generating new growth.
Collect your will tree cuttings or whips. These can come from any healthy willow tree and need to be about 1/4 to 1/2 inch thick and about 6 inches long or at least have four buds on them. Place them into water immediately so that their cut ends do not dry out. As soon as you separate them from the mother tree, they will start producing a rooting hormone that will cause them to start producing roots.
Prepare a potting container to hold them while they start rooting. It should be as deep as the cuttings are long. You do not have to be very particular about the kind of soil, as the willow whips will root very easily, just make sure the water has a way to drain.
Poke the soil with a long stick and slide the cuttings into the hole until you have buried them. Plant as many cuttings as the container can hold, keeping them about two inches apart from each other. Press the soil in around them.
Water the planted cuttings until it comes out from the bottom of the container. Place the container in a warm place for two weeks or until you see leaves sprouting up. Make sure the soil does not dry out during that time.
Empty the container near the site where you plan on planting the willow seedlings either permanently or for the next year. They should grow well in large (two 3-gallon plant pots) if you are not ready to place them in the ground. You should plant them in an area where they have plenty of water, but not near underground pipes. Separate each of the cuttings from the others carefully, so you do not damage the roots.
Dig a hole or poke a hole into the planting site or container and carefully set the rooted cutting in place. Firm the soil gently around it and water well. If the willow grows very quickly, you may have to stake it up the first year or two for support until the trunk is thick enough to hold the weight of the branches.