Advantages of Proportional to Flow Fertigation, include:

• Accuracy of Proportional to Flow Fertigation systems is (with proper design) very high.

• The placement of the fertilizer can be very accurate, within the effective root zone, not below the root zone.

• Soil salinity and soil pH management become more manageable.

• In contrast to application of dry granular fertilizer products, discreet control of the Proportional to Flow applied fertilizers exists. Once dry granular products are applied to the field, they are not retrievable. They remain present in the field until mineralized or leached and/or assimilated by the crop. If conditions are not ideal, nitrogen leaching can occur and  pose a hazard to groundwater quality.

In contrast, frequent application of as little as 1 to 5 pounds per acre of nutrient element at each or alternate irrigation events can save fertilizer, protect groundwater (with correct placement, in the effective root zone) and save money, since the irrigation system supplies the energy to deliver both the water and the fertilizer.

• Adjustments in fertility status can be accurately done, in accord with the physiological stage of development of the crop;  vegetative growth, flowering, fruit set, maturation, etc. Often it is not desirable to have high fertility levels during the flowering and fruit maturation stage of many crops. Proportional to Flow Fertigation provides a new tool for precisely managing fertility and nutrition status in accord with physiological stage of development. For example, in cotton during the boll-fill stage, it is often desirable to increase potassium (and perhaps lower nitrogen). Discreet adjustment of feed rates for each nutrient element in accord with crop physiological stage becomes entirely feasible.

Growers interested in the Proportional to Flow approach to Fertigation should recognize there is a learning curve. It is best to contact  experienced advisors to assist in the evaluation of your specific circumstances.

Design criteria for configuration of appropriate Proportional to Flow Fertigation systems is the subject of a future article.

Contact Information: William D. Jones Agricultural Consultant CCA No. 63839, (559) 676-7645.