Zinnia
Zinnia: Sowing, planting and harvest calendar
Zinnia belongs to the daisy family, Asteraceae, and is best known in gardens for its colourful annual forms. Many cultivated varieties descend from Zinnia elegans, a species native to Mexico. Other species, including Zinnia angustifolia, and their hybrids add to this horticultural group. The name therefore covers related garden plants with considerable differences in height, foliage and flower heads.The upright stems branch and carry opposite leaves. In forms derived from Z. elegans, the leaves are usually fairly broad, lack a long stalk and have a somewhat rough texture. Narrow-leaved zinnias have a finer outline. Compact selections form low clumps, while tall varieties can exceed a metre. This variation in habit affects their role in a border as well as their value for bouquets. Their leaves provide a green background for the strongly coloured heads.What looks like one flower is actually a head containing many small flowers. Single forms show a…
