The hardiness of a plant is its sufficient robustness, a winter survival with prolonged frost and bad weather in each climate region. In addition to the low temperatures associated with cold stress for the plant and drought, wind load, Mature, temperature falls and the course of soil temperature play a role.
The term is mainly used in horticulture for plants that are drawn outside their natural range.
To Hardiness of plants
Temperature data for hardiness can vary greatly. To some extent they relate to the overall survival of the plant, but not all parts of the plant that take damage or die under certain circumstances. The decisive factors are also geographical parameters for the area of origin of each plant such as climate and vegetation zone, prevailing winds and the altitude of the natural range. These parameters are all the more significant, the more they differ from the climate in the area of use.
As a concrete measure of the Hardiness there for garden owners hardiness zones ( WHZ ). In Germany they range from 5b (cool, alpine region ) to 8a (warm, Rhine Graben). Of each plant can give a recommendation to the appropriate hardiness zone. In Bavaria there are also outside the Alps cool layers, such as with WHZ 6a near Rosenheim, Amberg and yard. The warmest regions with WHZ 7b to 8a are on the lower Main.
However, this classification is only a rough guide. Decisive for the winter hardiness is the particular microclimate. Even in cooler regions, cold-sensitive plants can develop well in a sheltered position. Especially, protection against cold East and north winds in winter survival increased significantly. For example, provide a range of hills, a hedge or wall of a house for significantly higher temperatures at the site - one reason for the traditional pull of trellises ( esp. for pear, apricot and peach) on the south side of farms.
" Hardiness " in other contexts
The word is also becoming increasingly involved in ordinary language, where it refers not only to plants. Are hardy and winterize The terms are almost synonymous terms, although the first term and the second refers only to plants on inanimate. So a grave from the cemetery flower is being winterized by only hardy plants left standing and resulting vacancies are covered with fir branches.
Even buildings in the open ( retaining walls, paths, cisterns, etc.) are now often referred to as hardy if they resist severe frosts. However, detailed technical terms for this are frost depth and penetration and frost resistance and frost resistance.