The way that this form of metamorphism works is that rocks are scraped against each other causing them to be ground into a powder. Then this powder is reformed due to the pressure in the zone and the heat caused by friction of the two rock surfaces.ocks are classified by the processes under which they were formed. The differences in formation account for variations in the appearance of the rocks and, with some practice, you can learn to recognize the different types by sight. Metamorphic Rocks are rocks that have changed form due to heat and pressure.
Growing 4 to 6 feet in height and width, both mophead and lacecap hydrangeas can be used as specimen plants, in mixed borders or in mass plantings. The mountain hydrangea (H. macrophylla subsp. serrata) is a subspecies of bigleaf hydrangea that has slightly smaller leaves and flowers (see image at right).
Hydrangea paniculata cultivars are not among them. They will grow rapidly in partial shade to full sun and will tolerate air pollution. These hydrangeas like organically rich soil with medium moisture that drains well. If you want a hydrangea tree to grow rapidly and flourish, do not plant it where it will be growing in the shade all day. A hydrangea in the shade may not blossom or will look scraggly.