Basic structure of dicotyledonous stem-Sunflower stem. Inner structure of dicotyledonous stem reveals epidermis, cortex and stele. Epidermis. Epidermis is protective in function and creates the outermost layer of the stem. Epidermis is a single layer of parenchymatous rectangular cells.
Culture. Plumbago is propagated from cuttings in the summer, but you can also grow it from seed. Plant plumbago in light, sandy, well-drained soils, spacing each shrub 36 to 60 inches apart to allow room to grow. If spaced properly, blue plumbago will naturally cascade in a fountain shape.
Plumbago auriculata 'Imperial Blue'. Growing in billowing drifts with breathtaking flowers, blue plumbago is an easy-care, showy shrub with cottage garden appeal. 'Imperial Blue' is the most popular cultivar, with butterfly-attracting blossoms in vibrant blue with a hint of violet.