Rutgers Gardens, New Brunswick, NJ - USA

Paeonia (peony or paeony) is a genus of flowering plants, the only genus in the family Paeoniaceae. They are native to Asia, Southern Europe and Western North America. Boundaries between species are not clear and estimates of the number of species range from 25 to 40.

Most are herbaceous perennial plants 1.5 - 5 feet (0.5 - 1.5 metres) tall, but some resemble trees up to 5 - 10 feet (1.5 – 3 metres) tall. They have compound, deeply lobed leaves, and large, often fragrant flowers, ranging from red to white or yellow, in late spring and early summer.

A sepal (pronounced /ˈsɛp(ə)l/ or /ˈsiːp(ə)l/) is a part of the flower of angiosperms (flowering plants). Collectively the sepals are called the calyx (plural calyces), the outermost whorl of parts that form a flower. The word calyx adopted from the Latin calyx, not to be confused with calix, a cup or goblet. Calyx derived from the Greek καλυξ a bud, a calyx, a husk or wrapping, from Sanskrit kalika, a bud. Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom. After flowering, most plants have no more use for the calyx which withers or becomes vestigial, however, some plants retain a thorny calyx, either dried or live, as protection for the fruit or seeds. Examples include species of Acaena, some of the Solanaceae, and the water caltrop, Trapa natans. In some species the calyx not only persists after flowering, but instead of withering, begins to grow actively until it forms a bladder-like enclosure around the fruit. This is an effective protection against some kinds of birds and insects, for example in Hibiscus trionum and the Cape gooseberry.

Morphologically both sepals and petals are modified leaves. The calyx (plural, calices, the sepals) and the corolla (the petals) are the outer sterile whorls of the flower, which together form what is known as the perianth.

In botany, a bud is an undeveloped or embryonic shoot and normally occurs in the axil of a leaf or at the tip of the stem. Once formed, a bud may remain for some time in a dormant condition, or it may form a shoot immediately. Buds may be specialized to develop flowers or short shoots, or may have the potential for general shoot development. The term bud is also used in zoology, where it refers to an outgrowth from the body which can develop into a new individual.