- Hosta do not come true from seed, so if you plant a hosta seed, it will likely not look like it's parent plant. So hostas create their own different varieties without human help.
- Humans step in and purposely cross pollenate flowers to try to create new breeds of hosta. Even though you never know what you will get when you cross pollenate, it's easy to do.
- Hostas will create their own sports.
- The science of using tissue cultures to create even more new, unusual hosta varieties has progressed far over time.
- Hostas are a very popular and easy to grow plant, therefore there are lots of collectors always looking for new varieties.
I know I am overlooking some obvious reasons, so why do you think there are so many varieties of hosta?