Vinyl siding, like other exterior surfaces, is not immune to dust, dirt and debris, including tree sap. Sap is a sticky substance that falls off tree branches and dries quickly onto your home's siding and other surfaces. The substance also mixes with dirt before it is completely dry. Failure to remove it from vinyl siding can result in it staining the siding permanently.
General Household Cleaner
A general household cleaner can break down and make tree sap soft enough to remove with a sponge or rag. Spray the sap thoroughly with the cleaner then scrub the substance off your home's vinyl siding. For heavy sap buildup, spray the cleaner and let it stand for five to 10 minutes then scrub. Use a dull putty knife to help aid in the breaking-up process. You can also use a "natural" or biodegradable product to break down and remove tree sap.
A citrus-based cleaner can soften and aid in dissolving tree sap on vinyl siding. Only purchase and use citrus-based cleaners that state "safe for use on vinyl" and test the cleaner first in an inconspicuous spot to see if it will dissolve your siding's color.
Linseed Oil and Mineral Spirits
Linseed oil and mineral spirits are two other chemicals that can soften and dissolve tree sap on vinyl siding. Use the two chemicals separately and wear a nose mask and rubber gloves when handling and using the chemicals. Linseed oil and mineral spirits are available at hardware, home improvement and paint supply stores as well as chemical supply stores. Use one or the other chemical. You do not have to use both linseed oil and mineral spirits to remove tree sap from your vinyl siding.
Commercial bug, tar and sap removers are available from hardware, home improvement and automotive supply stores for removing tree sap from vinyl siding. Follow any and all recommendations and directions on the cleaner's container and wear rubber gloves and a nose mask when using the products.
Apply the cleaner directly on the sap present on the vinyl siding or onto a soft rag or sponge. Let the chemical stand for five to 10 minutes then blot the sap thoroughly with the rag or sponge to remove the substance. Scrub any stubborn sap spots with a soft-bristle brush. Rinse your vinyl siding thoroughly with water to remove any chemical and sap residue. Let the siding air dry or dry it with an old towel or rag.