The purpose of irrigation is to supply adequate amount of water when rainfall is not sufficient or timely to meet the crops’ water needs. Since the 1980s, one of Dole’s priorities has been to develop a more scientific approach to better schedule the irrigation of bananas and to apply water only when and where necessary as a way to compensate for water deficiencies in the soil.
In order to assess the need for irrigation, several factors must be considered:
- Weather conditions such as rain, humidity, evaporation
- Weather forecasts
- Crop capacity for water absorption
- Water available in the soil
- “Allowable” water deficit for issues such as crop resistance
When new farming areas are in need of irrigation, the first step is to obtain information and guidelines for the production zone and begin planning based on its specific conditions.
Dole uses high-technology devices to measure water balance and soil moisture, which is now monitored at least once per week. This methods allows the Company to avoid under- or over-irrigation, ensure an even water distribution, conserve energy, reduce chemical leaks and decrease fertilizer usage in the irrigation system as a way to minimize negative impacts on the environment.
For some crops, proper irrigation planning contributed to a reduction in volume of water irrigated by 20-25%.
Many other methods exist to help minimize irrigation. For example, Dole’s California berry division is testing drip irrigation using multiple drip tapes in each bed. Uniformly distributing water helps reduce overall water consumption as compared to the standard practice of using a single drip tape.
For salad production in California, Dole pre-irrigates lettuce fields with the water used in the processing of packaged salads. In the Dole Packaged Foods divisions of the Philippines and Thailand, treated waste-water is used for field irrigation.
In addition, Dole constructs reservoirs that capture rainwater for irrigation and reduce the need to use deep well water.
Dole’s Technical Assistance programs for independent banana and pineapple growers worldwide have been integrated into Dole’s ISO 14001 certifications.