The answer to whether outdoor furniture can stay outside all year isn't a simple yes or no. It primarily depends on the material. True all-weather materials like powder-coated aluminum, teak, and certain high-density polyethylene (HDPE) resins can typically withstand winter elements, though a protective cover is still recommended. However, furniture made of wrought iron (which can rust), untreated steel, or standard cushions are vulnerable to moisture, cold, and UV damage and should be stored.
For furniture you leave outside, thorough cleaning and a waterproof, breathable cover are essential. Elevate pieces off wet ground to prevent bottom rot or rust. For storage, choose a dry, cool place like a garage or shed. Always clean and dry furniture completely before storing to prevent mold.
In summary, while high-quality all-weather furniture is designed for year-round use, taking protective steps or storing vulnerable pieces will significantly extend their lifespan and keep your patio looking great for seasons to come.