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.
Handsome erect or prostrate annuals with opposite or verti-cillate sessile or clasping leaves and solitary flower-heads on long peduncles. The ray-florets are normally five, and persistent, and the pappus consists of two bristles. The species are all American, and chiefly from Mexico. The name is commemorative.
Fig. 129. Zinnia elegans. (1/4 nat. size.)
1. Z. elegans (fig. 129). - In the wild form the flowers are usually of some scarlet shade, but under cultivation it has given birth to varieties with white, yellow, orange, pink, crimson, and purple flowers, and many intermediate tints and mixtures rarely seen in flowers. There are also 'double '-flowered varieties and a dwarf strain. One of the great qualities of this plant is the durability of its flowers.
Z. Mexicana, syn. Z. aicrea, and Z. Ghiesbrechtii, have orange flowers, the former of prostrate and the latter of erect habit. There are also other species, but none equal to the above.