This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
A genus of about 120 species, chiefly tropical. The following is the only one seen in cultivation in the open air in this country, and that is tender. The name is of Arabic origin.
1. G. spinosa. Caper-bush. - A half-hardy deciduous spiny straggling shrub with simple leaves and white flowers tinged with pink. Sepals and petals 4; stamens numerous. The fruit is a berry, elevated on a long stalk, containing numerous seeds. The flower-buds are the Capers of our tables. This is occasionally grown as a curiosity. It is a native of the Mediterranean region.