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.
Black WalnutToxicity. http://www.wvu.edu/~agexten/hortcult/fruits/blkwalnt.htm .accessed 29 December 2005. Good plants for under trees Azaleas and rhododendron, shown here at the MinnesotaLandscape Arboretum, are examples of plants that naturallygrow as under-story plants beneath trees.Tiarella, tulips, and hosta planted under trees, also shown atthe Arboretum are other good choices for under trees.lanting under trees: perennials andannuals A combination of annuals and perennials canmake an attractive shade garden. Planting under trees: perennials Select from the manyplants previouslyshown, such asspiderwort(Tradescantia spp.)with hosta, northernseaoats, sweetwoodruff, and sweetWilliam.