Pelargonium acetosum, mid August. Sometimes known as Sorrel crane's bill or Sorrel-leaved pelargonium. Originally described in 1753 as Geranium acetosum by Carl Linnaeus, the name was changed to Pelargonium acetosum by the French botanist Charles Louis L'Héritier de Brutelle in 1789.
It does not have attractively scented leaves. The epiphet acetosum is Latin for 'sour' and refers to the acid taste of the leaves.