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1 to 10 of 29 glossary items


Leaves that are slender and pointed in shape, needle-like.

Acid soil

A soil that has a high activity of hydrogen ions, which gives the soil a pH value below 7 and produces a yellow, orange or red reaction when in contact with universal indicator solution (see pH). Acid soils are suitable for growing ericaceous or calcifuge (lime-hating) plants.


Leaves that taper to a long point.


Leaf or petal that ends in a sharp point.


Aphid-like insects of the family Adelgidae that are found exclusively on conifers. They feed on the sap of the host tree and cause cone-like growths, which can stunt or kill twigs and, in severe infestations, disfigure ornamental trees.


Leaves pressed back flatly or lying flat to the stem.


A term most often used to refer to roots that grow from a stem above ground.


To loosen soil in order to relieve compaction, allowing improved drainage and movement of air.

Aerial roots

Aerial roots grow on the stems of plants, such as ivy. These may be used for support or the uptake of air and moisture.

Air layering

This technique encourages the production of roots from a stem in order to propagate a plant. Usually involves making a shallow cut in the stem and surrounding it with a sleeve of polythene, which is taped above and below the cut and packed with sphagnum moss or peat.

1 to 10 of 29 glossary items