Sorrel has a number of subspecies the one tha bears the red flowers is known as Hibiscus Sabdariffa,Roselle or Red Sorrel which the petals are normally used for jams and syrups and juice which can be described a bit more mellower than Cranberry juice.
There are over hundreds of species in the Oxalidaceae family most of which are commly known as Wood Sorrel which is also known as Oxalis, it is the largest varity of the wood sorrel family and petal color varies from white to pink, red or yellow.
Some of the subspecies are from the Rumex acetosa.... Acetosa,Ambiguus,Arifolius,Hibernicus,Hirtulus and Vinealis
Wood sorrel known as Spiraea Ulmaria is hermaphrodite (having both male and female organs)
Sorrel has an oxalic acid content of the leaves which in the case of using the leaves for internal use caution should be advised to the quantity used it is harmless in small quantities but can be poisonous if used in large quantities.
The leaves can be crushed and applied to wounds to act as an astringent.
From the magical point of view, Sorrel can be use for healing, health, spiritual healing, affection, joy and maternal tenderness.
It is associated with Venus and also with Fairies,Elvesand Woodland Spirits.
With any herb I would advise you go by their Latin name and not their common name, most times if you have the name on the packet your herb comes in, the Latin name is normally found under the common name in brackets and will help you find out which sub species you are using.