There is no certified “weed free” seed supplies available in BC. You must ask for a certificate of seed analysis from the seed supplier to ensure you don’t accidentally introduce invasive plants.
How to know if your seed is free of weeds Seed labels show the main species in a seed package, but do not show contaminants such as invasive species. Ask for a certificate of seed analysis from the seed supplier, and look for the key pieces of information shown below.