Irrigation for cucumber and tomato seedlings is guided by how much light the plants receive and their stage of development. This insight comes from Daniil Kostylev, a scientist, agronomist and nursery owner, who spoke with Lenta.ru about practical watering strategies in greenhouses and nurseries.
The agricultural expert argues against rigid irrigation schedules. Instead, he emphasizes monitoring light levels and plant growth to determine when and how much to water. Higher light exposure drives more photosynthesis and transpiration, which increases water demand. In bright, sunny conditions, irrigation may amount to about 10 liters per square meter two or three times weekly, while on overcast days water needs drop significantly or irrigation may be unnecessary.
Plant age and vigor play a crucial role as well. For young cucumber seedlings, Kostylev suggests watering greenhouse soil every three days with approximately three to four liters per square meter. Tomatoes at the same stage require a bit more water, around six to seven liters per square meter every five days. As the plants grow, both the frequency and the volume of irrigation should be increased to meet their rising water needs.
During the peak of summer, the water demand shifts. Mature cucumber plants generally receive about five to six liters per square meter per day when watering the soil, whereas tomato plants may require ten to twelve liters per square meter every two days. This pattern reflects the deeper root structure of tomatoes and their greater water uptake capacity.
Kostylev notes that the root architecture explains why cucumbers need more frequent watering at lower rates while tomatoes, with deeper roots, pull water from a larger soil volume. The result is a watering regime that aligns with how each plant explores the soil for moisture, supporting steady growth and healthy development.
In practice, growers should adjust irrigation schedules as the crop matures, the weather changes, and light conditions fluctuate. Consistent soil moisture is key to avoiding stress that can slow growth or reduce yields. While precise numbers provide a useful guide, field observations remain essential. Soil moisture should be checked regularly, and irrigation should respond to actual conditions rather than a fixed timetable.