2. The local summer garden/community theater. I help build sets and paint. Occasionally, I run the spotlights.
3. Your neighborhood's local botanical club. It's just me (a middle-aged man) and a bunch of old ladies who run something called "weed warriors" where we go to local parks and beaches and eradicate invasive species with great prejudice.
"But my neighborhood doesn't have a botanica..." I'm willing to bet it does, you just don't know about it.
4. The local volunteer fire department. I am a volunteer EMT and Firefighter who got started when I fell and injured my back and my barber showed up on the ambulance. I rehabbed (hence, the yoga) and got into shape and signed up. EMT-B is easy to attain and Firefighter-I is even easier. I do one shift per week on average, usually Saturday nights and gained an instant group of people from which to make friends.