Leaving your outdoor furniture exposed to the elements inevitably leads to the question of rust. The speed at which this happens isn't a simple number; it depends heavily on several key factors.
The primary factor is the material. Aluminum and stainless steel (particularly grade 304 or 316) are highly rust-resistant and can last for years, even in coastal, salt-laden air. Wrought iron is durable but will eventually rust if its protective finish is compromised. Regular steel furniture, unless it's galvanized or has a high-quality powder coating, can show signs of rust surprisingly quickly, sometimes within a single season, especially in harsh conditions.
Your local climate is another major accelerator. Furniture in humid, rainy, or coastal environments with salty air will rust much faster than furniture in dry, arid climates. Industrial areas with acid rain can also speed up the corrosion process.
Finally, the quality of the protective finish is critical. A thick, durable powder coat provides a robust barrier against moisture. Once this coating chips, scratches, or wears thin, the metal beneath becomes vulnerable. To slow down rust, place furniture in a covered area when possible, use protective covers during off-seasons or bad weather, and immediately touch up any scratches in the finish with matching paint. Choosing rust-resistant materials from the start is your best defense for long-lasting outdoor furniture.