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.
Shrub, Tree or Hedge. Spacing bay leaf trees depends entirely on how big you plan to let them get. Within the hardiness zone, bay leaf grows as a small landscape tree between 12 to 15 feet tall, though it can grow up to 35 feet tall. Space bay leaf 15 to 20 feet apart as landscape trees. Bay leaf works well pruned and maintained as a small landscape shrub, requiring a spacing of 7 to 8 feet between plants. You also can grow bay leaf as a hedge or screen by spacing the plants 3 to 4 feet apart.