Plimpton, who plays Virginia in the comedy, explained that the writing is never "cynical", "vicious" or "cruel".
However, she added that the show is also not "treacly or corny".
Plimpton told TV Line: "There's little danger - I hope - of watching an episode and seeing some fake, plastered-on, sweetheart ending. It's not like you've watched 20 minutes of viciousness and buffoonery and people being jerks to each other, and have the last two minutes turned into a 'lesson' of some kind.
"Over the course of the show you're seeing these people who are on the same team. They love each other. They're all idiots, but they're all trying to figure stuff out together. There's something great about that, and it leaves room in the writing for it to be expansive, funny and honest."
Plimpton also revealed that she is happy playing a grandmother on the show, saying: "I guess it remains to be seen what happens after this, but I don't feel like [creator] Greg [Garcia] is aging me at all! I'm not walking away with a grey wig on and saying things like, 'Hey there, sonny!' I'm not playing older than I am, so that's good."
Raising Hope has been renewed for a second season and will return on Fox in the fall. The first season continues in the UK on Fridays at 9pm on Fox.
> Cloris Leachman becomes 'Raising Hope' regular