The epidermis of petals also form a variation of trichomes called conical cells. These cells all develop from the pavement cells, which make up the majority of the plants surface cells. In short, cellular differentiation of the epidermal cells is controlled by two major factors: genetics and environmental conditions.
Azaleas and rhododendrons thrive in acidic soil. Azaleas and rhododendrons thrive in the acidic soil that is common under pine trees. Both plants are classified under the genus Rhododendron; the main difference is the smaller, funnel-shaped flowers on the azalea.ake soil samples from the area under the trees where you want to plant the azaleas or rhododendrons. Mix the samples in a bucket and test with a soil pH test kit.
Dwarf Rhododendrons. The enormous rhododendron family, which includes both rhododendrons and azaleas, contains many dwarf plants suitable for rock gardens, their specific use depends on their soil and light preferences and their habits of growth--compact, spreading or trailing.. nakaharai (dwarf azalea) â 1', -5F. It forms a low dense mound that seems to grow flatter as it matures, since its ultimate height is 6 to 9 inches, while its spread is 12 to 15 inches. The small, shiny leaves, 2 inches long, are hairy on the undersides.