Glossary of Gardening Terms

Index H

Habit:
   General form of a plant.
Habitat:
   Environment in which a plant lives.
Haft:
   Narrow or constricted base of an organ, particularly the fall and standard petals of Iris flowers.
Hair:
   Unicellular or multicellular outgrowth of epidermis.
Half-Hardy:
   Able to withstand temperatures down to 0C (23F).
Half-pot:
   Container that is only half the depth of a standard plantpot.
Half-Standard:
   Standard tree or shrub with a clear stem of 1-1.5m (3-5ft) from ground level to the lowest lateral branches.
Hardening:
   The processes of becoming hardy to low winter temperatures.
Hardening off:
   Gradual exposure of tender seedlings to an environment of increased environmental stress, to toughen them prior to transplanting to field conditions.
Hardiness:
   capacity of a plant to withstand adverse conditions in general usage.
Hardpan:
   The impervious layer of soil or clay lying beneath the topsoil.
Hardwood:
   Mature wood used for cuttings.
Hardwood Cutting:
   Cutting taken from mature wood from early autumn (after leaf drop) to early winter.
Hardy:
   The condition of being well adapted to survive extreme winter cold. Native prairie plants are usually very hardy, while introduced species are less hardy
Hastate:
   Spear-shaped.
Heel Cutting:
   Cutting consisting of vigorous sideshoot from a stem of the current seasons growth, with a small piece of bark or older wood attached.
Heeling in:
   Temporarily setting a plant into a shallow trench and covering the roots with soil to provide protection until it is ready to be permanently planted.
Herb:
  

Plant with practical properties, such as culinary or medicinal use.

Botanically; any herbaceous plant.
Herbaceous:
  Any plant which is non-woody.
Herbaceous Border:
   Area of land set aside for the growing of herbaceous plants.
Herbaceous perennial:
   A plant in which the root lives three or more years and the aboveground parts die back to the root each winter.
Herbicide:
   Any pesticide used to control plants.
Hermaphrodite:
   Containing both male and female sex organs; bisexual.
Hesperidium berry:
   A type of berry with a tough rind that is easily peeled. (e.g., grapefruit)
Hip:
   Fleshy fruit of a rose.
honeydew
   The sticky secretion produced by sucking insects such as aphids.
Hormone:
   A chemical substance which is produced in one part of a plant and transferred to another part of a plant where it directs growth and development in very low concentrations.
Horticulture:
  The branch of agricultural plant science dealing with cultivation of fruits, vegetables and any plant grown for ornamental purposes.
Host:
   Any plants invaded by a parasite, and from which the parasite obtains its nutrients.
Hothouse:
   Artificially heated structure, usually glazed, for the growth of plants belonging naturally to warmer climates.
Houseplant:
   Plants, usually native to tropical climates, that are grown in houses or other heated buildings as ornamentals.
Humidity (relative):
  The amount of water vapour in a given quantity of air expressed as a percentage of the total amount of water that air could hold at that temperature.
Humus:
   Decomposed organic matter in soil.
Hybrid:
   A plant produced by crossing related but different parent plants.
Hybrid vigour:
  The increased vigour, growth or yield found in the offspring when genetically different parent plants are crossed.

Hydroculture: (Hydroponics)

   System of cultivation in liquid nutrients.
Hyphae:
   The threadlike strands of a fungus.
Hypogenous:
   Superior ovary Having the stamens, petals and sepals arise below the ovary.

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