If your wicker furniture is looking grimy, you can clean it with steam. Although its typically recommended that wicker furniture be cleaned carefully with sudsy water, you can steam clean wicker as long as you only steam a small section at a time and quickly dry it after you're done. As a whole, wicker likes humidity, but too much moisture can cause the wicker to become too malleable, making the furniture lose its shape and strength. Do not steam clean painted wicker furniture. The steam can cause the paint to peel.
Vacuum the surface of your wicker furniture to remove any dust.
Use a small, soft-bristled brush, like a toothbrush, to scrub away any built-up dirt in crevices or other small spaces.
Use a hand steam cleaner, like you use on countertop surfaces, to clean the wicker a section at a time. Repeat the process until you've cleaned the entire piece of furniture.
Use a hair dryer to dry off your wicker piece. Your wicker furniture should be dried as soon after steaming as possible to avoid making the wicker too malleable and limp.
For best results, steam your wicker piece of furniture outside on a sunny, windy day. The piece will dry as you work, removing the need to dry it with a hair dryer.
Clean your wicker furniture periodically with steam. Do not use steam on your wicker every day, as this could cause the wicker reeds to become too malleable and limp and make the furniture lose its shape.