Everything You Should Know About Patina & Surface Stains

Landscape lighting fixtures are usually placed in locations that leave them exposed to their environment and must be constructed with that in mind. VOLT Lighting designs all of its fixtures so they will continue to function through these environmental issues, but what we cannot prevent is some external cosmetic changes that can arise. The two most common aesthetic dilemmas that can occur on landscape lighting fixtures are hard water stains and patination on the fixtures’ surface.

What causes surface stains?

Surface stains are a result of residue that is resting on the surface of the product. These discolorations are purely superficial and do not indicate any compromise or defect in the product. Surface stains usually occur due to a fixture placement near a source of untreated water. Minerals dissolved in the water build-up on the fixture over time results in deposits of calcium and magnesium carbonates, which many find unappealing. Nearly any surface exposed to these conditions can form surface stains. However, they are often seen on landscape lights since fixtures are typically placed in close proximity to potential surface stain sources like sprinkler systems. The deposits only impact the cosmetics of the landscape lighting fixture and can be removed using one of the techniques below.

What causes patina?

Patination is the process that causes the surface of a material to change color over time. Patina is the term used to describe this phenomenon in a variety of metallic compounds, but the most common patina encountered in landscape lighting is on the exposed surfaces of brass and copper fixtures. On copper and brass, patinas are a result of the surface layer of the metal chemically reacting to the carbon dioxide, sulfates, and water found in the surrounding environment and atmosphere. This process occurs slowly over time but can be accelerated if saltwater or other corrosive substances are present. This is why patina is practically unavoidable, as the only way to completely prevent a patina forming would be if the fixture was in an area that had absolutely no moisture or exposure to our carbon dioxide-rich atmosphere. Patinas typically result in a light green tint to the exterior of a fixture, but this should not be a cause for concern.

Patinas do not compromise the integrity of the metal in any way. In fact, patinas actually enhance a fixture in a number of ways. For example, patinas actually prolong the life of the metal by adding a harder protective layer which combats the metal’s corrosion. The value of a patina as a protective layer has been known in the architectural community for centuries. The prime example of this being the Statue of Liberty, the American landmark that is constructed almost entirely of copper. Without its protective green patina, the monument would have been structurally compromised and collapsed years ago due to the corrosive saltwater surrounding it. One unique attribute of copper and brass patina is its anti-fungal properties. That means the patina will help prevent the growth of unsightly fungus on your outdoor lighting fixture. Additionally, many people actually desire a patina on their landscape lights as it gives the fixture a natural beauty that helps it blend into their landscape. Some will even try to accelerate the patination by treating the copper or brass with chemicals prior to installation in order to gain the advantages previously listed.

How to clean your fixtures

All that being said, there are those who prefer the more polished look their outdoor fixtures had before the patina or surface stains began to form. If that is the case, owners can temporarily reverse these issues by cleaning the surface of the fixture using one of the processes we have outlined below. Please note that while stains can be removed, they will most likely reoccur over time unless the fixture is relocated to an area that is protected from the issues that caused the staining. One should also remember the copper or brass will continue to patina regardless of where a fixture is placed. Every time that the patinaed layer is removed you also remove a portion of the copper or brass that the landscape light is comprised of, making it slightly more susceptible to future issues.

Cleaning with Soap and Water

Cleaning the fixture with soap and water is the easiest way to remove blemishes from the surface of your fixture. This is the best method for removing hard water stains without stripping off the patina.

1. Fill a small bowl with a solution of water and dish soap
2. Soak a cloth or sponge in the soapy water and scrub the desired areas
3. Let the mixture sit for 1-2 minutes after scrubbing
4. Scrub off any remaining residue using the abrasive side of the sponge or by firmly scrubbing with a cloth
5. Rinse the fixture with clean water and repeat this process until the desired result is achieved

Cleaning with CLR (Calcium, Lime & Rust Remover)

Cleaning the fixture more powerful products can risk damaging the finish or harming the surface if too abrasive of a medium is used to clean the product.

1. Clean the fixture with the basic cleaner like soap and water to remove debris.
2. In a well-ventilated area, mix equal amounts of CLR and warm water.
3. Apply directly to the affected area with a cloth or sponge and let soak for 2 minutes.
4. Rinse with cold water and clean cloth or sponge and repeat this process until the desired result is achieved.

*NOTE: Overuse of CLR can result in the deterioration and peeling away of a fixture’s finish (sparing use recommended).

Cleaning with Brasso

Brasso is a cleaning solution specifically designed for removing the tarnish or patina from the surfaces of metals like brass and copper. This is a more intense cleaning method and will expose the raw metal that previously resided underneath the patina. Please note that this is only a temporary solution and may negatively impact the fixture’s longevity by exposing the untreated metal.

1. Place a small amount of Brasso directly onto a sponge or cloth
2. Use the sponge or cloth to scrub the fixture’s surface until the desired level of polish is reached
3. Rinse the polished areas thoroughly with a clean rag and water, ensuring no Brasso residue is left behind on the fixture