Our ‘A’ to ‘Z’ of Gardening Terms

Terms that begin with “N”

NThe chemical symbol for nitrogen.
nastic movementA movement of a plant part (such as a leaf) not caused by an external stimulus.
native plantA plant indigenous to a specific habitat or location.
natural selectionThe action of the environment on organisms such that those better able to survive environmental stress are more likely to survive and reproduce.
naturalize(1) To design a garden with the aim of creating a natural scene. Planting generally is done randomly, and space is left for plants to spread at will. (2) The process whereby plants spread and fill in naturally.
necrosisTissue death.
nectarA sugary fluid secreted by some flowers.
nectar guideA contrasting color pattern on a flower that guides pollinators to the nectar.
nectaryA gland secreting nectar.
nematocideA material that kills or protects against nematodes.
nematodeA microscopic roundworm, usually living in the soil. May feed on plant roots and can be disease pathogens or vectors. Others are beneficial parasites of insect pests.
nitrate (NO3–)A plant-available form of nitrogen contained in many fertilizers and generated in the soil by the breakdown of organic matter. Excess nitrate in soil can leach into groundwater. See nitrogen cycle.
nitrifierA microbe that converts ammonium to nitrate.
Nitrogen (N)A primary plant nutrient, especially important for foliage and stem growth.
nitrogen cycleThe sequence of biochemical changes undergone by nitrogen as it moves from living organisms, to decomposing organic matter, to inorganic forms, and back to living organisms.
nitrogen fixationThe conversion of atmospheric nitrogen into plant-available forms by Rhizobia bacteria living on the roots of legumes.
nodeThe point on a plant where a branch, bud, or leaf develops. On younger branches, it usually is marked by a slight swelling. The space on the stem between nodes is called an internode.
nonpoint sourceA relatively small, nonspecific source of pollutants that, when added to other sources, may pose a significant threat to the environment. See point source.
nonselective pesticideA pesticide that kills most plants or animals.
N-P-KThe acronym for the three primary nutrients contained in manure, compost, and fertilizers. The N stands for nitrogen, the P stands for phosphorus, and the K stands for potassium. On a fertilizer label, the N-P-K numbers refer to the percentage of the primary nutrients (by weight) in the fertilizer. For example, a 5-10-5 fertilizer contains 5% nitrogen, 10% phosphorous, and 5% potassium.
nucleusThe organelle (structure) within most living cells that contains the chromosomes which controls various cellular processes, including division into new cells. Bacteria and viruses do not have a nucleus; their chromosomes are distributed throughout the entire organism.
nutrientAny substance, especially in the soil, that is essential for and promotes plant growth. See macronutrient, micronutrient.
nymphThe immature stage of an insect that undergoes simple metamorphosis. Usually similar in form to the adult.