Here's some advice, from the experts at Lumiere,
located in Westlake Village, California, on keeping your outdoor-lighting fixtures in shape:
Periodic cleaning can help reduce calcium deposits from water falling on fixtures and lenses. If the deposits are heavy, use a household cleaner formulated to remove lime.
Lubricate threads with an anti-oxidizing, antiseize lubricant like Permatex, found at auto-supply stores.
Lubricate the socket and lamp base with a high-heat silicone compound to prevent metals from corroding together, which makes it tough to unscrew a lamp.
Check fixture mounts to make sure they are secure, safe and not causing damage to trees or other landscape features.
Verify that landscaping and vegetation are not shielding the fixture and blocking the light. You may have to move fixtures or trim plants.Shown:
Smaller garden elements, such as flower beds and ground covers, can be highlighted with spreadlights or short bollards.