Indeterminate inflorescence, characterized by pedicles emerging from the axis, each ending in a flower. (Also see Cluster and Inflorescence).
Radicle
Root of the embryo in flowering plants.
Rattlesnake Calathium
Red Ginger
Alpinia Purpurata
Rhizome
Ground stem, usually horizontal and almost always underground, from which emerge leaves, lateral shoots and roots. Normally constitutes a storage organ allowing the plant’s survival during a short period of drought. Example: Begonia rex. The rhizome is a modified stem, subterranean or superficial, characterized by the accumulation of reserves and the provision of scales and buds: generally produces floral scape when flowering.
Rock garden
Bed or garden created with natural or artificial rocks, where one generally places plants that prefer calcareous soil, like carnations.
Root
Bottom part of a plant, usually underground; serves to maintain the plant firm and extract nutrients and water from the soil. There are two basic types of root: the fine and fibrous; the large and pivotal. The majority of plants have on or the other type of root; few present both. The root is the plants organ of fixation and absorption of water and nutrients, generally underground.
Rootstock (or simply, stock)
Plant upon which another plant (the scion) is grafted.
Rose (rose color)
Rosette
Distribution of flowers that eradiate from the same center. E.g., African violet.
Cactus: Fleshy plant, almost always originated in the Americas, common in deserts (although not restricted to them) and, with very few exceptions, whose leaves have been replaced with spines which emerge from areoles.