Our ‘A’ to ‘Z’ of Gardening Terms

Terms that begin with “G”

gallA growth on plant stems or leaves caused by abnormal cell growth stimulated by the sucking of some insects (e.g., aphids) or by viral, fungal, or bacterial infection.
gameteA sex cell, male or female.
geneA unit of genetic inheritance.
genusA group of related species, each of which is distinct and unlikely to cross with any other. A group of genera forms a family, and a group of families forms an order. See species.
geotropismThe turning or curving of a plant’s parts in response to gravity. A root growing downward is an example. Geotropism is controlled largely by the hormone auxin.
germinationThe initial sprouting stage of a seed.
germination inhibitorA chemical substance preventing seed germination.
girdlingThe cutting, removing, or clamping of bark all the way around a trunk or branch. Sometimes, girdling is done deliberately to kill an unwanted tree, but often it results from feeding by insects or rodents. Wires and ties used to support a tree can cause girdling, as can string trimmers.
glabrousHairless, but not necessarily smooth.
glaucousCovered with a grayish, bluish, or whitish waxy coating that is easily rubbed off. Blue spruce needles are an example of glaucous leaves.
gradual metamorphosisSee simple metamorphosis.
graft unionSee bud union.
graftingThe act of inserting a shoot or bud of one plant into the trunk, branch, or root of another, where it grows and becomes a permanent part of the plant.
gravitational waterWater in excess of a soil’s capacity. Drains downward to groundwater.
green coneAn enclosed composting unit often used for composting food waste.
green manureSee cover crop.
groundcoverPlants used in lieu of grass for holding soil and providing leaf texture.
growing seasonThe period between the beginning of growth in the spring and the cessation of growth in the fall.
growth regulatorA compound applied to a plant to alter its growth in a specific way. May be a natural or synthetic substance. See hormone.
guard cellLeaf epidermal cells that open and close to let water, oxygen, and carbon dioxide pass through the stomata.
gumA sticky, water-soluble plant secretion that hardens on contact with air.
gymnospermA member of a class of plants that forms seeds in an exposed condition, often in cones.