Which factor is the trigger for budburst timing?

Which factor is the trigger for budburst timing?

• A. Soil moisture
• B. Air temperature (>10C)
• C. Pruning date
• D. Grape variety

Answer: (B)

Budburst is driven by warmth. When air temperatures rise and stay above about 10°C, metabolic processes resume, cells begin to expand, and shoots begin to grow. That warm-temperature threshold acts as the signal that dormancy has ended and conditions are suitable for growth, which is why this is the best choice. Soil moisture, pruning date, and grape variety can influence when growth happens indirectly or vary by context, but the primary trigger is reaching a warm enough temperature, typically around 10°C.

Budburst is driven by warmth. When air temperatures rise and stay above about 10°C, metabolic processes resume, cells begin to expand, and shoots begin to grow. That warm-temperature threshold acts as the signal that dormancy has ended and conditions are suitable for growth, which is why this is the best choice. Soil moisture, pruning date, and grape variety can influence when growth happens indirectly or vary by context, but the primary trigger is reaching a warm enough temperature, typically around 10°C.