Compound leaves in which all the leaflets arise from a common petiole, recalling the open fingers of a hand
Palmate
Term used to name compound leafs with several leaflets that open like a fan from a common point, with the format of a flat hand. E.g., buckeyes.
Panicle
Type of inflorescence formed by a large cluster of pedicled flowers (with short stalk); compound inflorescence in which from a main axis other secondary axes sprout that bear flowers.
Parakeet Flower
One of the many varieties of Heliconia. Also called Parrot’s beak.
Parasite
Plant that extracts nourishment from the sap of another plant.
Pedicle
Stalk sustaining flower
Peduncle
Stalk sustaining an inflorescence
Peltate
Having the petiole outside the margin of the leaf.
Perennial
Preserves the adult form for more than two years. Plant that can live an indefinite period. Perennials can be herbaceous or woody. (See also annual and biannual)
Pergola
Garden structure formed by two parallels rows of columns that support horizontal trellis and that support climbing plants.
Petal
Generally the most showy part of the flower. Petals product the core of the flower and, when colorful, serve to attract pollinating insects towards the stamens and pistils. A flower can present few petals, like the flowers of several dayflowers, with only 3 petals) or several (like roses). The group of petals in a flower is called a corolla. (Also see sepal, stamen, pistil, flower and corolla).
Petiole
Connecting stalk between the leaf blade and its point of insertion in the stem or branch.
pH
Symbol to express the level of acidity, on a scale of 0 to 15, in which 7 represents neutrality (equilibrium between acid and alkaline). Values higher than 7 represent increasing alkalinity, and below increasing acidity. To have an idea, vinegar has a pH around 3 and sodium bicarbonate a pH around 8. Ornamental plants usually require a pH between 6 and 7.5 (each unit of Ph represents an acidity or alkalinity 10 times greater: a soil with pH 5 is ten times more acid that a soil with pH 6; a soil with pH 8 is 10 times more alkaline that a soil with pH 7).
Phalaenopsis
Phalaenopsis is one of the most refined orchids, also known as Moth Orchid, or by the abbreviation Phal.
Phalaenopsis (spike)
Phalaenopsis is in spikes that can have up to 25 flowers.
Photosynthesis
Process by which carbon dioxide is transformed in carbohydrates, inside the leaf, from light activating on chlorophyll – the green pigment – of stalks and leaves.
Pinching
Pruning method, also known as pinching back, entails removing soft buds, with the thumb and indicator finger, to induce branching growth
Pincushion Protea
One of the many variations of the protea family, also known as leucospermum.
Pink Cone Ginger
Alpinia Purpurata
Pinna
Individual section, generally known as follicle, of a very segmented leaf or frond. Used in the description of fern fronds. (Also see frond, follicle, pinnate).
Pinnate
Term used to describe a compound leaf divided in some or several pairs of opposed pinna (follicles). For example: palms.
Pistil
Female flower organ, including the stigma, style and ovary. (Also see stigma, style, ovary, flower)
Pollen
Dust produced and contained in the anthers, composed by minute grains that attach to a stigma and produce a tube that grows through the style and reaches the ovary where it fertilizes an ovule and gives rise to the formation of a fruit.
Pom-Pom
This variety got its name because of its shape.
Propagule
Plant material, for instance, a cutting from a stem or a leaf, used for the purpose of plant propagation.
Protea
Got its name in homage to the Greek god Proteus.
Pruning
Technique for removing, by cutting, branches or other parts of a plant with the purpose of eliminating dead or superfluous tissues, or controlling size and stimulating other reactions favorable to development and preservation.
Pseudobulb
Part of an epiphytic orchid’s stem with a bulbous aspect.
Pseudofruit (or Accessory fruit)
Structure that develops from flowers, but in fact does not develop from an ovary. Cashews, apples and quince are pseudofruits because they are not derived from the ovaries; strawberries, because they are derived from the several ovaries of a single flower; pineapple, raspberries and figs develop from different parts of several flowers.
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.