Adrian Grenier is known for being an environmental activist in his personal life — but the actor has also been trying hard to bring those same passions to the set of his hit series on HBO, Entourage. Unfortunately, such changes have been slow to develop.

“It’s a constant struggle, it’s about habits. We are habitual creatures and people don’t always want to change. They only want to do what they know,” Grenier told FOX News at the Salvatore Ferragamo soiree in Beverly Hills to support GlobalGiving’s Italy Earthquake Recovery and Relief Fund. “At one point, we wanted to use all bio-diesel generators on-set, but its just not viable as the technology isn’t up to par. So what we did was just replace one generator. It’s a slow process of transformation.”

In his personal life, however, things are greener than ever. “The fact that the Obama’s put a garden at the White House is not only a symbolic gesture, but it’s also a very tangibly successful one. I just put in a garden myself, I was inspired,” he added. “I’m growing zucchini, lettuce, tomatoes, strawberries and corn.”