J R Peter’s Part A Updates

Though farmers have been using straight fertilizers (elemental products containing one or two plant-relevant compounds) for ages, preblended fertilizers undeniably offer a number of advantages. Preblended fertilizers are bagged fertilizers derived from multiple straight fertilizer inputs, intended to reduce labor costs and offer crop-specific nutrition. Blended fertilizers are often used in combinations of two to three blends to provide complete nutrition. Jack’s Fertilizers is an industry pioneer when it comes to fertilizer blends, as they have been blending crop specific formulas in Allentown, PA since 1947. Their Jack’s Nutrients Part A blend and 3-2-1 plans have been a consistent presence for growers over the years. Recently, new blends have been introduced to build the Part A Series.



5-12-26 Part A – This is the familiar Part A that growers know and love. This blend remains unchanged but has received some label updates. Every Part A label now provides an elemental concentration breakdown for a 150 ppm N mix using both Part A and Part B. With this additional info, growers can feel confident they know exactly what their plants are receiving.

6-6-26 Low Phos Part A – Recent research in the horticultural industry has provided new guidance on phosphorus management. Luxury levels of phosphorus do not benefit plants and instead flow directly down the drain and away from our crops. The Low Phos Part A accommodates this new knowledge. When providing 50 ppm N, only 22 ppm P is present.

8-10-26 Strawberry Part A – Growing strawberries hydroponically in the greenhouse is becoming a popular choice for many food producers. This Part A formulation was developed based on Dr. Chieri Kubota’s extensive research on hydroponic strawberry production. Meant to be used at a much lower rate specific to strawberries (45ppm N) in conjunction with Part B, this feed and schedule provides complete nutrition from start to finish.

Whether you’re growing hydroponically or in container production, there’s definitely a Jack’s Fertilizers blend for you. Additionally, Griffin’s GGSPro team can build a customized fertility plan utilizing the most appropriate blends for your production. Check with your Griffin sales rep today for more information about specific blends, or to hear more about the fertility programs for greenhouse production!