In a study on growing raspberries in drip irrigation systems, different watering levels were tested in a Bulgarian village. They compared full watering, 20% less, and 40% less watering to see how it affected raspberry growth. The weather determined how often the plants needed water and how much.

Overall, higher raspberry yields were seen with full watering, leading to about three times more fruit compared to not watering. The best productivity, with 4.3 kg of raspberries per cubic meter of water, was achieved with 40% less watering than the full amount. This shows that using water more efficiently can still produce good raspberry harvests.