The Best Time for Watering Grapes
As a perennial vine plant, the water management of grapes directly affects the quality and yield of the fruit. Scientifically grasping the watering timing not only promotes root development but also avoids growth issues such as fruit cracking and blossom drop. This article systematically analyzes the four key water demand periods of grape growth based on agronomic research results.
Watering Guide for Grape Growth Cycle
Water Regulation During Germination Period
Complete the first irrigation within 7-10 days after the vines are unearthed in spring, maintaining soil moisture at 60-70%. Using drip irrigation to supplement 20-30mm of water during this stage can promote even bud germination. In northern regions, special attention should be paid to preventing late spring frosts, and it is recommended to irrigate 12 hours before the arrival of cold air to increase soil temperature.
Water Management During Flowering Period
Conduct 20-25mm of infiltrative irrigation 10 days before flowering, maintaining air humidity around 65%. Immediately after flowering, supplement calcium and magnesium water-soluble fertilizers, with the soil EC value controlled between 1.2-1.8mS/cm. Using zonal and segmented irrigation can effectively prevent the spread of gray mold disease.
Irrigation During Berry Expansion Period
Enter the critical water demand period at the early stage of fruit color change, requiring 30-40mm of irrigation per week. It is recommended to use pressure-compensating drippers to keep the moisture content of the soil at 40cm deep stable at 22-25%. Water deficiency at this stage can lead to a 15-20% decrease in single fruit weight and hinder sugar accumulation.
Water Control During Maturation Period
Gradually reduce water supply 20 days before harvest, lowering the soil moisture content to below 18%. Controlling the day-night temperature difference at 10-12°C can promote anthocyanin synthesis, and excessive irrigation can reduce soluble solids by 2-3 Brix. Using a tensiometer can accurately determine the timing to stop watering.
By establishing a model of grape phenology and water demand and implementing precise management with an intelligent irrigation system, the utilization rate of water and fertilizers can be increased by over 40%. It is recommended that grape growers regularly monitor soil moisture and adjust irrigation strategies according to the characteristics of different varieties (such as the large water requirement of the Kyoho series), achieving dual improvements in quality and yield.