I've done about every possible search I can think of, on both Google and Wikipedia, but it seems this sort of information is not in demand enough to be easily searchable.
My main character is a botany enthusiast. He reads academic journals on the subject, as well as any books he can get his hands on, and grows quite a few plants in his apartment that, while maybe not exotic, aren't the usual fare for casual gardeners and plant enthusiasts. But he's not a botanist in the professional sense. Instead, he works as a salesman at a furniture store.
What I need is information about what kinds of organizations at the local level offer events, lectures, gatherings, outings, etc., for people interested in botany. Not necessarily for professionals in the field, but for amateurs and enthusiasts as well. My story takes place in the state of Ohio, though that probably won't affect the answers I'm looking for. I'm not looking for specific groups, just what kinds of groups and organizations are out there for people in non-professional capacities.
Thanks for any help anyone can give, and let me know if you need any further information!