Some willow varieties are thicker, stronger and suited for furniture, baskets for firewood and even for small boats known as coracles. Salix viminalis grows to between 8 and 9 feet and looks like bamboo. Salix tiandra "White Newkind" produces olive green rods that can grow to between 6 and 8 feet long. Salix alba x frag "Jaune Hative" begin at the base of the rod with olive green, move through yellow to bright red tips. Salix tiandra "Faux Plant de Tourraine" is light brown at its base becoming dark chocolate brown.
Some weaving jobs require smaller, finer rods. There are numerous varieties fit for more delicate work and they come in many colors. Salix purpurea "Dark Dicks" grows 6 to 7 feet and is a deep reddish purple variety. "Franny's White" has light gray-green bark accented with reddish-black bud scales. "Welsh White Willow" comes in light beige to mottled brown. Salix nigircans "Faucille" is a dark black variety.
According to the University of Kentucky most willow sold for wicker is imported from overseas. If you plan to make baskets or furniture frequently you might consider growing your own. Cuttings are sold online and should be planted directly into moist well-drained soil amended with compost. Plant in the early spring in a spot with full sun. The following spring you can take cuttings of your own plants, replant them and in a few years you'll have an established stand of willow you can harvest for weaving.
Willows are deciduous and rods are harvested after leaves drop in the fall until just before bud break in the spring. Rods used for weaving are processed in a number of ways. Those with interesting bark colors are dried as they are picked. White varieties are stripped of bark before drying. Some light brown types are dried and then boiled prior to the bark being removed. Before weaving all dried rods are boiled.