PALMATE LEAF: Five or more lobes arising from one point - hand-like.
PARASITE: Any plant that grows upon another. It steals its moisture and nourishment from its host.
PARTERRE: Ornamental garden beds that have been geometrically designed and separated by walkways. Very common in Europe.
PASSALONG PLANTS: Plants that are shared between friends or club members and not easily found in catalogs.
PARASITIC PLANT: A plant which lives on, and acquires it's nutrients from another plant. This often results in declined vigor or death of the host plant.
PEA GRAVEL: Gravel about the size of a pea.
PEAT: The preserved and compressed remains of dead bog plants. Often known as peat moss because it is from sphagnum or sedge peat.
PERENNIALS: plants that do not die after flowering, but live from year to year.
PEAT MOSS: The partially decomposed remains of various mosses. This is a good, water retentive addition to the soil, but tends to add the acidity of the soil pH. Valuable for its pronounced air- and water-holding capacity and its freedom from weeds and disease organisms.
PEAT POT: Compressed peat into a pot that can be used for starting seeds. When planting times comes this entire pot can be put in the ground and the roots will grow through the pot as it decomposes.
PELLETED SEEDS: Seeds that have been coated with an inert material to make the handling of the seed easier
PERENNIAL: A plant which will live for three years or more under normal conditions.
PERFOLIATE: Paired leaves which fuse around the stem.
PERGOLA: Sometimes called an arbor, or walkway covered with trellis work. Usually climbing plants will cover this hardscape feature.
PERLITE: A mineral, which when expanded by a heating process, forms lightweight, porous white granuals. Perlite is a good addition to container potting mixes, to promote moisture retention while allowing good drainage. No nutrient value.
PERMACULTURE: A very advanced system of trying to grow and provide food by using perennial plants instead of the annuals the agriculture world uses now for most of our food.
PEST: Any insect or animal which is detrimental to the health and well being of plants or other animals.
PETAL: a whorl of structures that surround the inner reproductive organs of a flower. Together they are called the corolla. They often attract insects by color or nectar, facilitating pollination.
PETIOLE: A leaf stalk.
pH: pH is a measure of the acidity or basicity of a solution. Solutions with a pH less than 7 are considered acidic, while those with a pH greater than seven are considered basic. pH 7 is defined as neutral because it is the pH of pure water at 25 °C.
PHOTOPERIODISM: The response of plants to the length of a day and night.
PHOTOSYNTHESIS: the production of sugar from carbon dioxide and water in the presence of chlorophyll, activated by light energy and releasing oxygen.
PHYLLODE: A leaf stalk expanded to look like and act like a leaf.
PICOTEE: Term applied to a narrow band of color on a pale ground at the edge of a petal.
PINCHING BACK: Utilizing the thumb and forefinger to nip back the very tip of a branch or stem. Pinching promotes branching, and a bushier, fuller plant
PINCHING OUT: The removal of the growing point of a stem to induce bushiness or to encourage flowering. Also known as stopping.
PINNATE LEAF: A series of leaflets arranged on either side of a central stalk.
PIONEER PLANTS: The very first species to grow of the soil has had a traumatic occurrence, like a fire, flood or earthquake.
PIP: Two distinct meanings - the seed of some fruits and the rootstock of some flowering plants .
PISTIL: The female part of the flower, consisting of one or more carpels and enclosed ovules.
PLANT WINDOW: Double window with plants grown in the space between.
PLANTLET: A small plant off the original plant. A good example is the piggy back plant these will easily root. Used in propagation.
PLANT LICE: This is a reference to aphids found in British publications.
PLEACHING: a popular technique of training and pruning shrubs and trees into a wall.
PLUG: A small but well-rooted seedling raised in a cellular tray.
PLUNGING: The placing of a pot up to its rim outdoors in soil, peat or ashes.
POCKET GARDEN: A small growing area planted with miniature and dwarf varieties.
POLLEN: The microspores that carry the male gametophyte of seed plants.
POLLINATOR: Any being, insect or creature such as bees, moths, butterflies, animals and insects that move from plant to plant.
POTAGER: A vegetable garden planted in a formal and ornamental style.
POLLINATION: the transfer of pollen from the anther to the stigma.
POT-BOUND: A plant growing in a pot which is too small to allow proper leaf and stem growth.
POTPOURRI: A mixture of sweet smelling leaves, petals, blooms to create a perfume in a room.
POTTING ON: The repotting of a plant into a proper-sized larger pot which will allow continued root development.
POTTING MIX: Pre-packaged ready-to-use soil mixture that may include sand, compost, vermiculite, and peat moss.
POTTING SOIL: A soil mixture designed for use in container gardens and potted plants.
PRAIRIE GARDENING: Specifically creating a garden of plants from the Midwestern states of the U.S.
PRE-EMERGENT WEED KILLER: Using a herbicide to kill weed seeds to prevent them from germinating.
PRESSURE-TREATED WOOD: Wood which has been impregnated with preservatives to resist decay. Use with caution in vegetable gardens or where edible foods/fruits are grown.
PRICKING OUT: The moving of seedlings from the tray or pot in which they were sown to other receptacles where they can be spaced out individually.
PROPAGATION: This refers to the many different ways to start new plants. This included various methods of starting new plants ranging from starting seeds to cuttings or layering.
PRUNING: The cutting and trimming of plants to remove dead or injured wood. Used to control and direct the new growth of a plant, increase quality or yield of flowers or fruit. Also to ensure growth position of main branches to enhance structural strength, beauty and to avoid winter damage.