Apparently she's from the new 90210, which I haven't caught. But those curls! Love!
I'm told that her on-set stylist, Dyana Aives is using Big Curls Curl Defining Creme by Samy. It works by amplifies curls by adding volume, texture and shine and is specially formulated to define, separate and extend curls.
The good news is that it's easy to find - you can pick yours up at Walgreens, Rite Aid, and CVS locations here in the US, and Canadians can grab it at Shopper's Drug Mart stores.