Digitalis purpurea range of colours from white through pink to purple, such as "Dalmatian Purple". Cultivated forms often show flowers completely surrounding the central spike, in contrast to the wild form, where the flowers only appear on one side. "D. purpurea" is easily grown from seed or purchased as potted plants in the spring. The following selections have gained the Royal Horticultural Society's Award of Garden Merit: "Digitalis purpurea" is hardy to zones 4-9. Digoxigenin (DIG) is a steroid found exclusively in the flowers and leaves of the plants "Digitalis purpurea" and "Digitalis lanata". It is used as a molecular probe to
Plant as rayon and acetate derived from plant cellulose. Thread used to sew cloth likewise comes in large part from cotton. Thousands of plant species are cultivated for aesthetic purposes as well as to provide shade, modify temperatures, reduce wind, abate noise, provide privacy, and prevent soil erosion. Plants are the basis of a multibillion-dollar per year tourism industry, which includes travel to historic gardens, national parks, rainforests, forests with colorful autumn leaves, and festivals such as Japan's and America's cherry blossom festivals. While some gardens are planted with food crops, many are planted for aesthetic, ornamental, or conservation purposes. Arboretums