1. Online retailers: Many online retailers, such as Amazon, Etsy, and eBay, sell catnip seeds. You can find a wide variety of catnip seeds from different sellers, so you can compare prices and read reviews before making a purchase.
2. Garden centers: Most garden centers sell catnip seeds. You may also be able to find catnip plants at garden centers, which you can grow for your own cat.
3. Pet stores: Some pet stores sell catnip seeds. You may also be able to find catnip toys and treats at pet stores, which can help keep your cat entertained.
When purchasing catnip seeds, be sure to read the instructions carefully before planting them. Catnip is a hardy plant that can be grown in most climates, but it does best in sunny locations with well-drained soil. You can plant catnip seeds indoors or outdoors, but it's best to start them indoors a few weeks before the last frost date in your area.