I'd like to get more into gardening, what's the best way to learn about theory online?
user
There are lots of books you can find in your local library or on Amazon, and some videos you can find online.  I'm also happy to recommend a particular book I've used and enjoyed myself.
assistant
I'd like to get more into gardening, what's the best way to learn about theory online?
user
I can help you with this.  I know what's good!  I like the show “A Science Odyssey”, hosted by Morgan Freeman.  That might be a good place to start.
assistant
I'd like to get more into gardening, what's the best way to learn about theory online?