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).
Many of the plants that produce flowers in clusters are tropical plants that require warmer climates to thrive, but some will tolerate cooler temperatures under the right conditions. Clusters of blooms make great cut flowers for arrangements or a simple centerpiece. The hydrangea is a perennial flowering shrub that sports large clusters of small flowers. While there are 23 species of hydrangea, there are only five species that are typically grown in the United States. The most common being the Hydrangea macrophylla species.