Glossary of Gardening Terms

Index G

Garden Compost:
   Humus rich material formed by the decay of organic matter. Used as a mulch or to improve soil structure and nutrition.
Genetic engineering:
   The artificial manipulation of genes under in vitro conditions with the goal of introducing specific genetic changes.
Genus:
  The first word in a binomial name. A genus usually contains several to many closely related species. The genus name is always capitalised and written in italics, or underlined.
Germ:
   Embryo.
Germination:
   Physical and chemical changes that occur as a seed begins to develop into a young plant.
Gibberellins:
   A class of growth promoting hormones which overcome many forms of dormancy, and lead to cell elongation.
Girdling:
   The choking of a branch by a wire or other material, most often in the stems of woody plants that have been tied to tightly to a stake or support.
Glabrous:
   Smooth and hairless.
Gland:
   Cell or cells secreting various substances such as oils.
Glaucous:
   With smooth, blue-green bloom.

Globose:

Globular:

   Spherical.
Glochid:
   Small, barbed bristle or hair borne on the areole of a cactus.
Glucose:
   A simple sugar that serves as fuel source for nearly all organisms. It is generated during photosynthesis and converted to form all other more complex forms of carbohydrate.
Glume:
   One of the two bracts which enclose the spikelet in a grass inflorescence.
Glumella:
   Inner glume or palea.
Graft-hybrid:
   Plant resulting from the combination of tissues from both scion and rootstock.
Grafting:
   Method of propagation by which the scion of one plant is united with the rootstock of another to form one plant.
Granulated Bark:
   Bark ground to a fine , medium or coarse grade, often used as a mulch or in compost.
Grass:
   Member of the Gramineae family.
Greens:
   Leafy vegetable crops which are usually eaten cooked .(e.g., Spinach)
Greenhouse:
   Structure glazed with glass or plastic, providing a controlled atmosphere in which to grow plants etc.
Green Manure:
   Practice of sowing quick growing crops with the intention of digging them into the soil to improve fertility and/or soil structure.
Greenwood cutting:
   Cutting taken from a shoot tip of a plant once the initial flush of spring growth has slowed. The stem is slightly harder than a softwood cutting.
Grex:
   collective term for progeny of artificial cross from known parents of the taxa family.
Ground Cover:
   Usually applied to low growing plants that quickly spread over the ground, helping to prevent weeds.
Ground frost:
   Climatic effect when the temperature at or just beneath the surface of the soil falls to 0C (32F) or below.
Group:
   Category of cultivated plants that denotes a collection of similar, named cultivars.
Growing Point:
   (shoot-tip) Tip of a shoot from which new extension growth develops.
Growing Season:
   Part of the year when a plant is actively growing.
Grow On:
   To grow young plants to a stage where they are ready to plant out or flower.
Growth Habit:
   (see Habit)
Growth retardant:
   A non-hormonal chemical substance which interferes with the formation of movement of growth promoting hormones, leading to reduced plant growth.
Guard cells:
   Pairs of specialised epidermal cells which regulate the size of a stomatal openings. The guard cells take up water and swell to close the stomates.
Gymnosperm:
   A seed plant with seeds which are not enclosed in a fruit when mature.
Gynoecium:
   The female parts of a flower; the pistil.

Last updated 10 March, 2002
© copyright 1999, P. A. Owen