Clean that hard to clean Siding!
To remove dust and cobwebs from siding, use a garden hose with a sprayer attachment. To remove heavier grime, look for an all-purpose house wash in a container that attaches to your hose. Or use a long handled scrub brush and a slightly sudsy solution of dishwashing liquid and water. Wash from the bottom up, and rinse from the top down.
If mildew is present on your wood siding, ask your paint dealer to recommend a house wash that includes a mildewcide. After washing, allow the house to dry for at least two to three days in dry weather before repainting.
Another tip from www.maidsway.com.