The admission record shows that she was ill and destitute, and she was admitted by the Relieving Officer (RO).
Records for the Edgware workhouse (later known as the Redhill Institution) up to the 1940s are held at London Metropolitan Archives, as part of the Hendon Board of Guardians series (BG/H), but relatively few are online for these later dates. Inmates were often transferred between workhouses, as their needs, or those of the institution, changed.
You will probably need to get research done at LMA, either by their paid research service or by someone visiting there on your behalf. Perhaps try posting a request on the London and Middlesex lookups board, linking to this thread?
http://www.rootschat.com/forum/london-middlesex-lookup-requests/ADDED - she was apparently discharged 6 weeks later, on 10 October 1913, at her 'own request' (indexed as Jeffress). No destination stated.