Ashton began entering poetry slams at the age of seventeen, and won the London Poetry Slam Championship in 2000. In 2006 she was Young Writer in Residence at the Contact Theatre in Manchester. Her first play, Harm's Way, was shortlisted for the Verity Bargate Award in 2007, and premiered at the Lowry, Salford in 2008 as part of the National Youth Theatre’s new writing season. Her other plays have included Skunk, performed by the National Youth Theatre and Soho Theatre; and She from the Sea, performed in 2010 at the London International Festival of Theatre (LIFT). Ashton was co-writer of Suddenlossofdignity.com, Bush Futures Programme. One of her plays, For all Those Women who Thought they were Mad, was selected to be part of the Royal Court Playwriting Festival in 2009. Ashton contributed to the writing of The Children's Monologues, adapted from over 300 original stories by Tswana, Zulu and Sesotho children in South Africa and presented by Dramatic Need in 2010. She has worked with the Bush Theatre and the Clean Break theatre company.