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OFFSET – A young plantlet which appears on a mature plant. 

OPEN POLLINATED – Any plant that has been pollinated in the field.

ORGANIC – Fertilizers and chemicals that have been obtained from a source which is or has been alive. A type of gardening using no chemical or synthetic fertilizers or pesticides.

ORNAMENTAL – A plant that is grown strictly for its foliage or flower rather than for food or any other economic use.

OVER POTTING – Repotting a plant into a pot which is too large to allow successful establishment.

OVERSEEDING – Planting on top of an existing garden or lawn. Rye grass over lawns for winter. Wildflower seed in meadows.

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PARASITE – Any plant that grows upon another.

PARTERRE – Ornamental garden beds that have been geometrically designed and separated by walkways.

PEA GRAVEL – Gravel about the size of a pea.

PEAT – The preserved and compressed remains of dead bog plants.

PEBBLE TRAY – A tray filled with pebbles to create humidity in the environment.

PELLETED SEEDS – Seeds that have been coated with an inert material just 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.

PERLITE – Granular volcanic rock, used to improve the aeration in potting soil. 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.

PETAL – One of the divisions of the corolla – generally the showy part of the flower.

pH – The scale where the acidity and alkalinity of soil is measured. It starts at “1″ for acid and goes to “14″ for alkali. Most gardens will fall between 5.5 – 8.6.

PHOTOPERIODISM – The response of plants to the length of a day and night .

PINCH OUT – Pinching with the fingers to remove the tip of a growing shoot to encourage lateral growth.

PIONEER PLANTS – The very first species to grow of the soil has had a traumatic occurrence, like a fire, flood, earthquake.

PIP – Used in propagation. The side offshoot of a rootstock. A good example is lily of the valley.

PLANTLET – A small plant off the original plant.

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 for covering large areas as in ground covers or lawns.

POCKET GARDEN – A small growing area planted with miniature and dwarf varieties.

POLLEN – The yellow dust produced by the anthers.

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 UP – Taking the young seedlings or transplants into a specific container for mature growth.

PRE-EMERGENT WEED KILLER – Using a herbicide to kill the weed seeds to prevent them from germinating.

PRESSURE TREATED LUMBER – Lumber that has been treated with chemicals to prevent rotting.

PROPAGATION – Refers to the many different ways of starting new plants.

PRUNING – The cutting off leaves or branches within limits in order to remove dead or diseased foliage or branches.

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RADICUMS – These plants are special in that their stems have roots that will cling as they grow vertically or grow over the ground.

RAISED BED – Any ornamental or vegetable bed that has soil higher than the surrounding immediate area.

REED – Tall grasses that grow in shallow water.

REMONTANT – Plants that will bloom more than once a year.

RE-SEEDING – Plants that drop their seeds for next season.

RESTING PERIOD – A period of dormancy where energy is restored to the plant.

RETAINING WALL – A wall that has been built on a slope to keep the soil from sliding or eroding.

REVERT – Sometimes a particular cultivar might change back to one of its original species.

RHIZOME – A thickened stem which grows horizontally below or on the soil surface, as in iris rhizomes.

ROCK GARDEN – An area constructed of larger rocks arranged to look natural.

ROOT BALL – Matted roots plus enclosed soil within the pot of a container grown plant or when plant material is transplanted.

ROOT-BOUND – Often, when plants are left too long in their container, the roots become entangled and begin to grow in circles.

ROOT CROPS – Any vegetable that the roots are edible: i.e. carrots, potatoes, turnips.

ROOT CUTTING – Plants that grow away from the mother plant and root, can be dub up and transplanted.

ROOTING HORMONE – A chemical in powder or liquid form which promotes the formation of roots at the base of a cutting.

ROOT PRUNING – This is done in two instances. One when repotting from one pot to another, roots that have grown in a circle are trimmed to promote future growth.

ROOT ROT – Quite common in plants that are effected by fungus diseases and have poor drainage.

ROOTSTOCK – The roots and stems arise from this part of the plant.

ROOT ZONE – The entire area where roots are growing below the plant.

ROTATION – Specifically towards crop rotation: changing the plants in the same growing area.

ROTENONE – Material used a lot by organic gardeners.

RUNNER – A creeping stem which produces small plantlets along its length.