Regular monitoring and timely replacement ensure that birds get fresh and nutritious suet. The recommended frequency for changing suet is generally every 1 to 2 weeks. However, this can vary based on temperature, bird activity, and suet quality. Warmer weather may require more frequent changes every 2/3 days to prevent melting and spoilage. If you notice signs of spoilage like melting, mold, or a foul odor, it's important to replace the suet immediately.