puhkeaeg

Puhkeaeg is a term used in horticulture and phenology to describe the period during which dormant plant buds break dormancy and begin visible growth, marking the transition from winter to spring. The concept is commonly applied to fruit trees, ornamental shrubs, and other woody plants, where the timing of bud burst influences subsequent development, flowering, and harvest.

The onset of puhkeaeg depends on several factors. Temperature is primary: a sufficient accumulation of heat after a period of cold, often expressed as growing degree days or chill portions, signals buds to wake up. Photoperiod (day length), moisture, and weather conditions such as late frosts can modulate the exact timing. Different species have varying chilling requirements and heat needs, leading to species-specific and site-specific puhkeaeg windows.

In practice, puhkeaeg is used for forecasting and management. Farmers and horticulturists monitor bud burst to schedule pruning, irrigation, fertilization, and pest or disease control. Frost risk assessment around puhkeaeg is important, because a late frost can damage new growth and affect yield and quality. Models that combine chilling and warming trends help predict when puhkeaeg will occur and how it may shift with climate variability.

Overall, puhkeaeg is a key reference point in the study of plant phenology, linking weather conditions to the timing of early growth stages and their agricultural implications. See also phenology, bud burst, vernalization, and growing degree days.