Hose down the siding.
How to use simple green siding cleaner.
In a bucket or large container mix 1 5 cups simple green oxy solve house and siding cleaner in a gallon of water.
The oxygen bleach will clean the vinyl.
Allow cleaner to dwell on surface for 3 5 minutes.
Never spray upwards under siding.
Clean in sections using a soft bristle brush.
Rinse with a hose from top to bottom.
If you are concerned about landscaping use a vinyl siding cleaner solution comprised of one gallon of water mixed with one cup oxygen bleach in a bucket.
In a clean bucket add 2 cups of simple.
Rinse at high pressure keeping the nozzle at least 2 feet from the surface and the spray perpendicular to the surface.
Use a soft bristle brush to apply the cleaning mixture in sections scrubbing firmly enough to clean without damaging.
Dilute 1 measure of simple green with 10 measures of ambient water example.
At low pressure setting apply simple green oxy solve to an area that is small enough to be rinsed before it dries.