A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechanism for the union of sperm with eggs . Flowers may facilitate outcrossing (fusion of sperm and eggs from different individuals in a population) resulting from cross-pollination or allow selfing (fusion of sperm and egg from the same flower) when self-pollination occurs. The two types of pollination are: self-pollination and cross-pollination. Self-pollination happens when the pollen from the anther is deposited on the stigma of the same flower, or another flower on the same plant. Cross-pollination is the transfer of pollen from the anther of one flower to the stigma of another flower on a different individual of the same species. Self-pollination happens in flowers where the stamen and carpel mature at the same time, and are positioned so that the pollen can land on the flower's stigma. This pollination does not require an investment from the plant to provide nectar and pollen as food for pollinators. Some flowers produce diaspores without fertilization (parthenocarpy). Flowers contain sporangia and are the site where gametophytes develop. Many flowers have evolved to be attractive to animals, so as to cause them to be vectors for the transfer of pollen. After fertilization, the ovary of the flower develops into fruit containing seeds. In addition to facilitating the reproduction of flowering plants, preserved flowers have long been admired and used by humans to bring beauty to the environment, and also as objects of romance, ritual, esotericism, witchcraft, religion, medicine, and as a source of food.
Hydrangea common names hortensia, is a genus of over 75 species of flowering plants native to Asia and the Americas. By far the greatest species diversity is in eastern Asia, notably China, Korea, and Japan. Most are shrubs 1–3 m (3 ft 3 in – 9 ft 10 in) tall, but some are small trees, and others lianas reaching up to 30 m (100 ft) by climbing up trees. They can be either deciduous or evergreen, though the widely cultivated temperate species are all deciduous. In most species, preserved hydrangeas are white, but in others (notably H. macrophylla), they can be blue, red, pink, light purple, or dark purple. In these species, floral color change occurs due to the presence of aluminum ions which are available or tied up depending upon the soil pH. For H. macrophylla and H. serrata cultivars, the flower color can be determined by the relative acidity of the soil: an acidic soil (pH below 7), will have available aluminum ions and typically produce flowers that are blue to purple, whereas an alkaline soil (pH above 7) will tie up aluminum ions and result in pink or red flowers. This is caused by a color change of the flower pigments in the presence of aluminum ions which can be taken up into hyperaccumulating plants. Lowering the pH of potting soils or mixes usually does not change the flower color to blue, because these soils have no aluminum ions. The ability 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, pink, or white. The flower color of most other Hydrangea species is not affected by aluminum and cannot be changed or shifted. Hydrangeas are also nicknamed 'Change Rose'.
Amaranthus is a cosmopolitan genus of annual or short-lived perennial plants collectively known as amaranths. Some amaranth species are cultivated as leaf vegetables, pseudocereals, and ornamental plants. Most of the Amaranthus species are summer annual weeds and are commonly referred to as pigweeds. Catkin-like cymes of densely packed flowers grow in summer or autumn. Amaranth varies in flower, leaf, and stem color with a range of striking pigments from the spectrum of maroon to crimson and can grow longitudinally from 1 to 2.5 metres (3 to 8 metres) feet) tall with a cylindrical, succulent, fibrous stem that is hollow with grooves and bracteoles when mature. There are approximately 75 species in the genus, 10 of which are dioecious and native to North America with the remaining 65 monoecious species endemic to every continent (except Antarctica) from tropical lowlands to the Himalayas. Members of this genus share many characteristics and uses with members of the closely related genus Celosia . Amaranth grain is collected from the genus. The leaves of some species are also eaten. Amaranthus shows a wide variety of morphological diversity among and even within certain species. Preserved amaranthus is part of the Amaranthaceae that is part of the larger grouping of the Carophyllales. Although the family (Amaranthaceae) is distinctive, the genus has few distinguishing characters among the 75 species present across six continents. This complicates taxonomy and Amaranthus has generally been considered among systematists as a "difficult" genus and hybridize often.
Craspedia is a genus of flowering plants in the family Asteraceae commonly known as billy buttons and woollyheads. They are native to Australia and New Zealand where they grow in a variety of habitats from sea level to the Alps. The genus is found in every state of Australia except the Northern Territory. In New Zealand, Craspedia is found from East Cape on the North Island south to Stewart Island. It also occurs on Campbell Island and the Chatham Islands. Craspedia are rosette-forming herbs with compound capitula borne on erect, unbranched scapes. The capitula are hemispherical to spherical heads of tiny flowers. Most species are perennial; one species is recorded as an annual (Craspedia haplorrhiza). The leaves have considerable variation in form, ranging in colour from white to green, and are often covered in fine hairs. Preserved craspedia is grown both as an ornamental garden plant, and floriculture for cut flowers and floral arrangements, including dried flowers. Africa is a source of exports.
Gypsophila is a genus of flowering plants in the carnation family, Caryophyllaceae. They are native to Eurasia, Africa, Australia, and the Pacific Islands. Turkey has a particularly high diversity of Gypsophila taxa, with about 35 endemic species. Some preserved gypsophila are introduced species in other regions. The genus name is from the Greek gypsos ("gypsum") and philios ("loving"), a reference to the gypsum-rich substrates on which some species grow. Plants of the genus are known commonly as baby's-breath, or babe's breath, a name which also refers specifically to the well known ornamental species Gypsophila paniculata. A few species are commercially cultivated for several uses, including floristry, herbal medicine, and food. The baby's-breath most commonly used in flower arrangements such as bouquets is the common gypsophila, G. paniculata. G. elegans is also used as a cut flower. The genus is a source of saponins that can be used for many purposes, including the production of photographic film and hemolytic laboratory reagents. Their detergent qualities make them useful in soap and shampoo.
