The first plant patent issued August 18, 1931, to Henry F. Bosenberg, on a Climbing or Trailing Rose:

A plant patent is granted by the United States government a distinct and new variety of plant (other than a tuber propagated plant or a plant found in an uncultivated state). The grant, which lasts for 20 years from the date of filing the application, protects the patent owner’s right to exclude others from asexually reproducing the plant, and from using, offering for sale, or selling the plant so reproduced, or any of its parts, throughout the United States, or from importing the plant so reproduced, or any part thereof, into the United States.

Plant patents are unique to the United States and supplement the protection provided utility patents and by the Plant Variety Protection Act.