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21 to 30 of 64 glossary items

pH

The symbol pH is followed by a number that indicates the degree of acidity or alkalinity of soils. Related to a standard solution of potassium hydrogen pthalate, pH7 is neutral. Numbers lower than 7 indicate acidity, while numbers higher signify alkalinity.


Phosphate

The second component of NPK. Phosphates may be sold as rock phosphate, super phosphate or triple super phosphate. Occurs naturally in banana skins, bone meal and dried blood.


Phosphorus

A non-metallic chemical element having the symbol P. Phosphorus is found in all animal and vegetable organisms, and is an essential plant nutrient, encouraging healthy root development. The P in NPK formulae.


Photosynthesis

The process by which plants convert energy from sunlight into food. See Chlorophyll.


Phylloclade

A branch having the form and functions of a leaf. Often the branch or stem will be flattened, resembling a leaf. Plants that have adapted to very dry conditions are usually phylloclads, eg, members of the cactus family.


Phylum

In classification, the category above class in the plant kingdom. It encompasses organisms of the same general form.


Picotee

Refers to flowers having petals with dark edging, eg, some varieties of carnations and tulips.


Pilose

Hairy. Having soft, sparse and fairly long hairs covering the leaf surfaces, producing a silvery sheen or downy appearance.


Pinching out

The method of stopping a plant growing upwards by removing the growing tip, thereby encouraging the development of side shoots.


Pinna

Of a fern frond, the primary division or leaflet of a pinnate leaf.


21 to 30 of 64 glossary items