PREMORSE: Appearing to be broken off at the end, as a root or stem.
PRICKING OFF: A method of transplanting tiny seedlings. The blade of a pocket knife or plant marker is used to remove each plant from one spot and move it to another.
PRICKING OUT: A method of thinning seedlings by cutting them off at soil level so as not to disturb the roots of the other plants.
PRICKLE: A small, spine-like point arising from the bark or epidermis of a plant, instead of from the wood.
PROCESS: In botany, this refers to an organic structure arising from the surface of a plant or plant part, such as a spine on a stem.
PROCUMBENT: Trailing or lying flat without taking root.
PRODUCTIVITY: The present capability of a kind of soil for producing a specified kind of plant.
PROFILE: A vertical section of the soil through all its layers.
PROPAGATING BENCH: This is a stationary, shallow box, usually filled with fine sand, but sometimes soil, which is kept moist. Cuttings or slips are inserted into the sand or soil until they form roots.
PROPAGATING CASE: A device used to root cuttings and raise seedlings. It could simply consist of a flowerpot or box covered with a glass pan, or be a specially constructed frame with brick or wood sides and a sliding or hinged sash (top).The purpose of this case is to provide a humid atmosphere, which prevents the cuttings from wilting before they've formed roots. To hasten the formation of roots, bottom heat is often provided by hot-water pipes or electric soil-heating cables. Less cuttings will fail, the faster the roots form.
PROPAGATION: The various methods by which plants are increased. Following are some different techniques of propagation: Seeds, division or separation, softwood cuttings or slips, grafting or budding, layering, etc.
PROPAGATOR: A structure that provides a humid atmosphere for seedlings, cuttings, or other plants being propagated.
PROPAGULE: A shoot, such as a sucker or runner, which may be used for propagation.
PROPHYLLUM: 1. A secondary bract on a flower stalk. 2. A two-edged initial bract on the flowering part of a plant.
PROSTRATE: Lying flat on the ground
PROTERANTHOUS: Having flowers that appear before the leaves of a deciduous plant, as in Jacaranda mimosifolia and many species of Prunus (which contains the Peach, Almond, Cherry, Apricot and Plum species).
PROTHALLIA: These are formed when spores come into contact with moisture. Prothallia are thin, green, heart-shaped structures that bear many root hairs which attach to the soil and extract nourishment. Underneath the prothallia, small male and female organs are produced. The male organ is small with two cilia (hairs) which propel it through a film of moisture to the female, where fertilization takes place. Once that happens, a Fern, which has a single Fern-shaped leaf, is produced and eventually grows into a complete plant.
PROTOGYNOUS: Having the stigma mature before the anthers.
PROTOGYNY: The condition of having the stigma mature before the anthers.
PRUINOSE: Having a frosty look due to a bloom or powder on the surface; said of certain plant surfaces, such as the undersides of leaves, or the surface of blueberries or grapes.
PRUNING: Trimming branches or parts of trees and shrubs, in order to strengthen those that remain or to bring the tree or plant into a desired shape. Root pruning is also practiced with a spade or other tool, in order to control size, promote fruitfulness, or secure a growth of fibrous roots near the stem prior to transplanting.