Both Rose mallow and Hibiscus acetosella are fine for you or your tort to eat.
Rose Mallow may refer to:
Any plant in the Lavatera genus; specially Lavatera trimestris
Any of several species in the Hibiscus genus, especially Hibiscus moscheutos http://en.wikipedia.org/wiki/Rose_mallow
Lavatera (I just bought this one at the CTTC Class) is a genus of about 25 species of flowering plants in the family Malvaceae, native to the Mediterranean region, central and eastern Asia, and Australia. A number of species previously listed in this genus have now been transferred to the related genus Malva. Lavatera species are known as tree mallows, or rather ambiguously as rose mallows, royal mallows or annual mallows. http://en.wikipedia.org/wiki/Lavatera
Hibiscus acetosella
In tropical and subtropical areas, the Chinese hibiscus (H. rosa-sinensis), with its many showy hybrids, is the most popular hibiscus.
About 200-220 species are known, including:Hibiscus acetosellahttp://en.wikipedia.org/wiki/Hibiscus
I grow rose mallow (H. moscheutos) for my torts and they love it. It is called hardy hibiscus as it is hardy to zone 5. H. acetosella is new one on me and I found it hardy to zone 8 and 9 (native to E. Africa) and as such would be treated as an annual in most areas. It is a very attractive plant and should be fine for torts. An other option is rose of sharon (hibiscus syriacus) which is also hardy.