To achieve optimal yields and superior fruit quality in cucumber cultivation, it is crucial to ensure that plants receive adequate and timely moisture throughout their growth stages. Cucumbers have shallow root systems, making consistent soil moisture essential, particularly during fruit setting and maturation. The goal of irrigation is to provide sufficient water to the plant roots without causing soil saturation, which can hinder root respiration.

Monitoring soil moisture regularly is key. Avoid waiting for visible signs of wilting before irrigating. Instead, dig into the soil to assess moisture levels and adjust watering schedules accordingly. Since cucumber water needs fluctuate with plant age and environmental conditions, a fixed weekly watering schedule is often ineffective. For instance, young cucumber plants in a greenhouse during cooler months may require irrigation only every 5-10 days, with water reaching 15-20 cm of soil depth. Conversely, during the warmer months, water requirements can increase significantly, necessitating more frequent irrigation.

Typically, cucumbers need about 25–50 mm of water per week, depending on soil type and growth conditions. Inconsistent watering, especially during key stages like flowering and fruit development, can negatively impact fruit quality, leading to issues such as nubbin or hooked fruit.

Water pH also plays a critical role in cucumber production. The ideal pH for nutrient solutions should range between 5.5 and 6.0. If water pH exceeds this range, adjustments are necessary: nitric, sulfuric, or phosphoric acids can lower pH, while potassium hydroxide can raise it. It is essential to correct the pH before adding fertilizers to prevent nutrient precipitation, especially in alkaline water sources.

Drip irrigation systems offer significant advantages over traditional irrigation methods. They provide precise control over water and nutrient delivery, which can enhance crop growth and reduce greenhouse humidity. This method is particularly beneficial in regions with limited irrigation water resources, as it minimizes water wastage and supports the use of reflective mulches, such as white polyethylene film.

In conclusion, effective cucumber irrigation involves a nuanced approach that adapts to changing plant needs and environmental conditions. Regular soil moisture assessment, careful pH management, and the use of efficient irrigation systems are all critical to achieving high-quality fruit and maximizing crop yield.