Basic Rose Terminology

Consulting Rosarian: Jolene Adams

When speaking about roses it makes it much easier if all of us use the same terminology. The following is a list of basic terms used to describe rose plant parts. It is a lot easier to understand what someone is talking about when they say "sepals" rather than "... you know, those little green things just under the flower ...".

• Anther - The upper portion of a stamen which contains the pollen sacs.
• Apical Meristem - Non-maturing cells located at the tips of shoots and roots which produce the plant hormone auxin.
• Auricle - The 'ear-like' projection found on the tip of the stipule.
• Auxin - a plant hormone that regulates the bloom cycle for rose buds.
• Axil - the angle on the upper side where the leaf and stem join.
• Axillary - A term applied to buds or branches occuring in the axil of a leaf. These buds begin to grow after pruning or deadheading.
• Bark - The outer layer of the stem of a rose.
• Bud - An embryonic shoot that may eventually produce either flowers of foliage.
• Bud Union - That area between the roots and the stems where the bud of the desired variety was grafted onto the rootstock.
• Bract - A leaf unlike the ordinary leaves which is usually smaller or of a different shape, growing from the peduncle just below the flower.
• Calyx - The first of a series of flower parts growing from the peduncle, composed of sepals, usually green and leaf-like.
• Cane - The stem of a rose, either the main stem (which then becomes the trunk) or lateral stems or branches.
• Carpel - An organ bearing ovules along its margins; part of a compound pistil.
• Compound Leaf - A leaf composed of two or more parts or leaflets. Rose leaves are pinnately compound.
• Corolla - The second of a series of flower parts growing from the peduncle, composed of petals.
• Double - Referring to how many petals the rose has - usually between 25 and 45.
• Filament - The stalk of the stamen which supports the anther.
• Floral Tube - A cup-like structure formed by the fusion of the basal parts of the sepals, petals and stamens. Don't call it a 'calyx tube.'
• Fruit - A ripe ovary containing seeds and any adjacent parts.
• Hip - The fruit of the rose which contains the seeds.
• Leaf - An organ arising laterally from superficial tissues of a shoot apex. It is usually flat and may be simple or compound.
• Leaf Scar - A mark left on the stem where the leaf detaches. There is a bud just above each leaf scar.
• Meristem - Tissue composed of cells that do not mature, but remain capable of further growth and division. Present in growing tips.
• Mixed Buds - Buds that produce both leaves and flowers; usual type of bud on roses; present in leaf axils.
• Ovary - The swollen basal portion of the pistil containing the ovules or seeds.
• Ovule - A struct containing the embryo sac, nucellus, integuments and stalk. After fertilization this develops into seeds.
• Peduncle - The main stem of a spray or of an individual flower.
• Pedicel - The stem of an individual flower in a spray.
• Perianth - The collective term for the calyx and corolla (sepals and petals) combined.
• Petal - One of the units of the corolla of the flower. Roses have from four to over 100 petals, depending on the variety.
• Petaloid - A transitional phase between petal and stamen. Petalloids are visible in single and semi-double roses as deformed looking petals in the center of the rose.
• Petiole - The stalk of the leaf.
• Petiolul - A subdivision of the petiole which connects the lateral leaflets to the petiole.
• Pistil - The central organ of the flower composed of one or more carpels and enclosing the ovules.
• Pith - The soft inner portion of a rose stem.
• Pollen - The granules within the pollen sacs containing genetic information used for sexual reproduction.
• Prickle - A spine-like superficial outgrowth of the stem. Roses have prickles, not 'thorns.'
• Roots - The underground parts of the rose used for support and to absorb water and nutrients.
• Rootstock - The cultivated roots of a rose which will be implanted with a bud from another variety (grafting).
• Semi-double - Referring to how many petals the rose has - usually 12 to 25.
• Sepal - One of the units of the calyx. These are the green coverings of a flower bud that open to reveal the petals of the rose. Roses usually have 5 sepals.
• Single - Referring to how many petals the rose has - usually four to eight.
• Spray - Several flowers buds which arise from one peduncle and develop into many flowers on short pedicels.
• Stamen - The organ of the flower producing pollen, composed of an anther and a filament.
• Stigma - The top of the pistil, the part that receives the pollen grains.
• Stipule - A leaf appendage that is usually present in roses on the petiole where it meets the stem.
• Style - The part of the pistil that connects the ovary and the stigma.
• Terminal - A term applied to buds occurring at the end of branches. The end or tip.
• Thorn - A branch of a plant that becomes woody, hard and pointed. Cactus plants have thorns, locust trees have thorns. Rose do NOT have thorns as the 'prickles' on a rose do not develop from 'branch' tissue.
• Trunk - The main stem of a rose, the cane that later produces all the side branches or lateral canes.
• Vegetative Bud - A bud that produces only leaves and never flowers. Roses do NOT have vegetative buds.