Generally, the vine needs a minimum rainfall per year: how many millimetres in cool climates and how many in warm regions?

• A. 750/500
• B. 500/750
• C. 600/900
• D. 400/600

Answer: (B)

Water supply to vines depends on climate because hotter conditions drive more water loss through evaporation and transpiration. In cool climates, temperatures are lower, so vines lose less water and can meet their annual needs with less rainfall—about 500 mm per year. In warm regions, the higher temperatures increase water demand, so more rainfall is needed—about 750 mm per year—to avoid drought stress. This is a general guideline; actual needs can vary with soil type, irrigation, root depth, and how rainfall is distributed during the year.

So the pairing is 500 mm for cool climates and 750 mm for warm regions.