Most art courses are media specific (like painting or sculpture), Environmental art is site specific. We make art for a location/context, but we can use whatever media we need.
Nope. I'd do sculptures, possibly design features for it, but I wouldn't do the actual gardening.
I'm interested in animal rights, so I recently did a sculpture about what would happen if we are humans, and sited it at a local abbattoir. We make work for a concept, a place or an event. The work is generally polictical, and can be permanent or a 'hit and run'.