Glossary of Gardening Terms

Index N

Narcotic:
   Inducing insensibility or drowsiness.
Native:
   Species that grows wild in a particular region.
Naturalise:
   Describes a species that apparently grows wild in a particular area but is introduced and not native.
Nectar:
   Sugary, liquid secretion that attracts insects to aid pollination.
Nectary:
   Gland, often a modified sepal, petal, or stamen, that secretes nectar.
Needle:
   Stiff linear leaf of a conifer.
Nervate:
   Leaves with prominent ribs or veins.
Net assimilation rate:
   The photosynthetic gains of a plant minus respirational losses. The decline of many house plants is due to a negative net assimilation rate, where respirational losses of energy or exceed photosynthetic gains.
Neutral:
   With a pH of 7.0, neither acid or alkaline.
Nitrogen fixation:
  The transformation of atmospheric nitrogen (N2) into plant-available form by action of Rhizobium bacteria usually living in nodules on the root systems of legumes.
Node:
  The point on a stem where a leaf would normally be attached.
Nodule:
  Swellings on the roots of legumes in which nitrogen fixation takes place.
Nomenclature:
  

Standard system of naming plants and providing for the formation and use of the names.

Cultivated plants are named in accordance with the International Code of Nomenclature for Cultivated Plants and the International Code for Botanical Nomenclature.

Non-infectious disease:
  A disease caused by an environmental factor and not a pathogenic organism.
Non-Vascular:
   Describes plants that lack conductive tissue for the circulation of water and nutrients, for example, fungi and mosses.
Non-Woody:
   Soft-stemmed.
Nucleus:
  A large membrane-bound organelle containing a cell's genetic information.
Nut:
  Dry, non-splitting fruit with a woody or leathery shell surrounding a single seed(kernel). (e.g., Hazel nut) .
Nutrients:
   Mineral necessary for healthy growth.

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