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.
Tap the plum seed with a hammer just enough to put a crack in the hull. This process, known as scarification, breaks the seed's dormancy and tells it that the time is right to germinate. Plant the seed 2 to 3 inches deep in the sand and perlite mixture using a plastic container and water it thoroughly.