Hydrangea (/ha?'dre?nd?i?/;common labels hydrangea or hortensia) is a genus of 70-75 kinds of flowering vegetation local to southern and eastern Asia (China, Japan, Korea, the Himalayas, and Indonesia) and the Americas. Certainly the greatest varieties diversity is eastern Asia, notably China, Japan, and Korea. Most are shrubs 1 to 3 meters tall, however, many are small trees and shrubs, yet others lianas getting up to 30 m (98 feet) by climbing up trees. They could be either evergreen or deciduous, although greatly cultivated temperate varieties are deciduous.Having been introduced to the Azores, H. macrophylla is currently very common, particularly on Faial, which is known as the "blue island" because of the vast number of hydrangeas present on the island.Life cycleHydrangea blooms are produced from early spring to late fall months; they increase in flowerheads (corymbs or panicles) frequently at the ends of the stems.
Typically the flowerheads contain two types of bouquets: small non-showy plants in the guts or interior of the flowerhead, and large, showy blossoms with large bright colored sepals (tepals). These showy plants are extended in a band often, or to the exterior of the tiny flowers. Plant life in wild populations typically have few to none of the showy flowers, while cultivated hydrangeas have been selected and bred to have significantly more of the larger type blooms.There are two flower arrangements in hydrangeas with Corymb style inflorescens, which includes the commonly grown "bigleaf hydrangea"--Hydrangea macrophylla. Mophead plants are large round flowerheads resembling pom-poms or, as the name implies, the comparative head of your mop. On the other hand, lacecap flowers bear round, flat flowerheads with a center core of subdued, small bouquets surrounded by outer jewelry of much larger plants having showy tepals or sepals.
The blooms of some viburnums and rhododendrons can show up, initially, comparable to those of some hydrangeas.Ground and colors acidityIn most species the blossoms are white, but in some species (notably H. macrophylla), can be blue, red, green, light purple, or dark crimson. In these varieties the colour is influenced by the presence of aluminium ions which are available or tangled up depending after the garden soil pH. For H. h and macrophylla. serrata cultivars, the flower color can be determined by the relative acidity of the soil: an acidic soil (pH below 7), will supply aluminum ions and typically produce flowers that are blue to purple, whereas an alkaline soil (pH above 7) will tie up aluminum ions and bring about pink or red flowers.
This is caused by a color change of the flower pigments in the presence of aluminium ions which can be adopted into hyperaccumulating vegetation.[6] Decreasing the pH of potting soils or mixes usually does not change the rose color to blue, because these soils have no aluminum ions. The capability to blue or pink a hydrangea is also influenced by the cultivar. Some plants are selected for their ability to be blued, while others are bred and selected to be red, white or pink. The flower color of most other Hydrangea species is not affected by aluminum and cannot be changed or shifted. Hydrangeas also have a nickname called 'Change Rose'.