Julia Roberts likes to "challenge" herself with knitting.

The actress stars in August: Osage County and is also a busy family woman with husband Daniel Moder and kids Hazel, Phinnaeus and Henry at home.

She's an avid knitter and rather than relaxing, she likes to push the boundaries with her patterns.

"I knit. Knitting is my favourite hobby," she told German magazine TV Movie when asked what she does when she has time to herself.

"Currently I'm working on a really complex scarf for my husband. Sometimes I really challenge myself!"

The 46-year-old had been keeping a fairly low profile prior to promotional events for her latest movie.

Julia says her family is all she needs these days and that parties don't really appeal to her.

"Since I have kids I just prefer being at home," she smiled.

"My private life completely fulfils me - nothing can compete with that."

Julia is one of the best-known stars in Hollywood thanks to films such as Pretty Woman and Notting Hill.

Despite this, she says her life is nowhere near glamorous, with her day starting at around 5.15am to take her kids to school.

"Four times a week I stay on and help out voluntarily for all kinds of things," she said.

"When I get home I tidy, put a wash on, prepare dinner...

"I like it best when we all sit together and chat about our days."