How can you produce blue patina on copper? The natural process of copper getting blue green patina in nature can be accelerated by using all natural exposing methods, most commonly using vinegar or ammonia, and salt. Copper can be sprayed, wrapped with different moist mediums or suspended in a container with these ingredients. The process can take anywhere from a day to a week to grow good amount of nice blue or green patina. There are also “fake” ways of producing natural looking patina, you can find many products now that create patina, generally just wipe on the metal and let develop.