Many people just have gardens without truly knowing what their plants even really are. Every year we get a lot of people adding daylilies to the lilium category and visa versa. Despite the category named Lilies (lilium), we get everything that has lily as a common name; Water lily, Peruvian Lily, or Princess Lily, Lily of the Nile, Blackberry lily, etc. We get camellias in the dahlia category. Cosmos in the hibiscus category. Admin tries to catch and move them to their correct categories before voting starts but don't always catch them all. I'm sure many think a gorgeous Epiphyllum certainly isn't a cactus and any passiflora bloom is tropical looking to them, despite any zone hardiness.
I understand your frustration, admin is always open to fine tuning the categories as they have done over the years since this contest has started. I enjoy the contest for what it is, not perfect but something fun, especially this year! It's something anyone can participate in whether a seasoned gardener or just a hobbyist photographer of their plants.
