overvintning

Overvintning, or overwintering, is the set of strategies used by organisms to survive the winter months in temperate and boreal climates. The term applies across multiple groups, including plants, animals and microorganisms, and describes life-history changes, physiological adaptations, and behavioral decisions that permit survival through cold or resource-scarce periods.

In plants, overwintering generally involves entering a dormant state or acquiring physiological cold hardiness that prevents damage from freezing temperatures. Perennials may store energy in roots, bulbs or tubers, shed leaves, or develop protective buds. Flowering plants often require exposure to a period of chilling before they can resume growth in spring. Horticultural practices to aid overwintering include selecting hardy varieties, mulching soil, windbreaks, and protective covers such as row covers, cloches, or insulated structures.

In animals, overwintering strategies range from behavioral to physiological. Some mammals hibernate or enter daily torpor, lowering metabolic rate and conserving energy. Insects may suspend development in a diapause stage, often aligned with day length and temperature. Others migrate to milder climates. Amphibians and fish may overwinter in brumation or by persisting in unfrozen water, employing antifreeze compounds or supercooling. Shelters, burrows, or deep water provide insulation.

In ecosystems, overwintering contributes to population dynamics and community structure, shaping predator–prey interactions and reproduction timing. In agriculture and horticulture, inadequate overwintering can cause winterkill or reduced yields, prompting breeding for hardiness and management practices to reduce frost damage.

Climate change alters overwintering conditions by shifting cold period duration and variability, potentially changing the timing of emergence, survival rates, and pest pressures.