Here is a good start on a project I've been working on for longer than I'd care to admit. It's a custom database for specific plants, bringing all the DB features of a particular plant and giving enhanced access to that information.
It's in beta right now and there is not much to see yet, but it'll greatly expand in the days ahead.
The big feature right now is a custom "Search by characteristics" engine. So, you can go into the Daylilies database and search based on ploidy, scape height, bloom traits, hybridizer, year of introduction, and things like that.
Here are some examples:
Daylilies
Roses
Clematis
Irises
Sempervivum
Jovibarba
Heucheras
Dahlias
Have fun playing around with that search.