Ask Mr. Smarty Plants

First of all, the plant must have been cultivated, or discovered in cultivation, by you. You must also show that the plant remains stable through asexual means of propagation such as cuttings, grafting, bulbs, rhizomes, tissue culture, etc. It is not possible to patent a sexually propagated plant, but for these you can apply for a "certificate of protection" under the Plant Variety Protection Act. Cultivar name registration and trademarking are also possibilities. You can read a summary of the process of patenting a plant from Texas A&M University's Aggie Horticulture page. The American Nursery and Landscape Association (ANLA) web page has a lot of information about patenting and trademarking plants prepared by the National Association of Plant Patent Owners (NAPPO). Be sure to click on the link plant patents and trademarks which will lead you to the 6-page PDF file, "Patents and Trademarks on Plants", that you can download. This article tells you not only about plant patents, but also about certificates of verification, cultivar registration, and trademarks for plants. For complete information on how to patent your plant the United States Patent and Trademark Office has an informative publication.