Gardening Glossary

~ G ~

A | B | C | D | E | F | G | H | I | J | K | L | M
N | O | P | Q | R | S | T | U | V | W | X | Y | Z

gall

A 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.

gamete

A sex cell, male or female.

gene

A unit of genetic inheritance.

genus

A 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.

geotropism

The 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.

germination

The initial sprouting stage of a seed.

germination inhibitor

A chemical substance preventing seed germination.

girdling

The 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.

glabrous

Hairless, but not necessarily smooth.

glaucous

Covered with a grayish, bluish, or whitish waxy coating that is easily rubbed off. Blue spruce needles are an example of glaucous leaves.

gradual metamorphosis

See simple metamorphosis.

graft union

See bud union.

grafting

The 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 water

Water in excess of a soil's capacity. Drains downward to groundwater.

green cone

An enclosed composting unit often used for composting food waste.

green manure

See cover crop.

groundcover

Plants used in lieu of grass for holding soil and providing leaf texture.

growing season

The period between the beginning of growth in the spring and the cessation of growth in the fall.

growth regulator

A compound applied to a plant to alter its growth in a specific way. May be a natural or synthetic substance. See hormone.

guard cell

Leaf epidermal cells that open and close to let water, oxygen, and carbon dioxide pass through the stomata.

gum

A sticky, water-soluble plant secretion that hardens on contact with air.

gymnosperm

A member of a class of plants that forms seeds in an exposed condition, often in cones.