Front Row Ag Part B 25 LB

What Part B Is

Front Row Ag Part B is a fully water-soluble dry fertilizer with a guaranteed analysis of 2.0% total nitrogen (all nitrate), 13.0% available phosphate, 17.0% soluble potash, 5.0% magnesium, and 7.0% sulfur. Source materials are potassium nitrate, monopotassium phosphate, potassium sulfate, and magnesium sulfate — a clean, salt-indexed input list with no ammoniacal nitrogen.

Part B is the second component in Front Row Ag's three-part system (Part A / Part B / Bloom). It handles the bulk of magnesium and sulfur delivery across both vegetative and flowering phases, while the precision-tuned phosphorus-to-potassium ratio supports vigorous growth and photosynthesis. The integrated magnesium load eliminates the need for a standalone Cal-Mag supplement when the system is run as designed.

The formula includes a proprietary acid component to maximize solubility and solution stability, plus surfactants that condition growing media over time for more consistent nutrient delivery. A food-grade blue dye allows visual confirmation that Part B is fully dissolved and properly diluted before delivery to the crop — a practical quality check in high-volume operations.

Who It's Built For

Part B in the 25 lb format is sized for commercial licensed cannabis and hemp facilities — indoor, greenhouse, and mixed-light — running continuous production cycles with automated or semi-automated fertigation. Whether your facility uses Dosatrons, Argus injectors, electric diaphragm injectors, Venturi injectors, pneumatic injectors, or operates direct-to-reservoir batch mixing, Part B is compatible with all of these delivery methods.

The dry soluble format gives purchasing managers and head growers predictable storage, simpler freight logistics compared to liquid nutrients at commercial volumes, and a longer shelf life without degradation concerns. For multi-site operators running standardized programs, the 25 lb bag integrates cleanly into the 3:2:2 and 4:3:3 mixing protocols that Front Row Ag publishes with EC-validation checkpoints, supporting consistency across rooms and facilities.

Part B is formulated to be compatible with a wide range of source water profiles. For hard water or alkaline water sources, Front Row Ag also offers a Hard Water variant with modified magnesium levels — confirm water chemistry before specifying which version fits your facility.

Key Formulation Features

Magnesium is fully built into the Part B formula, covering the plant's Mg demand throughout veg and flower without requiring a separate supplement. The high sulfur level (7.0%) works alongside nitrogen to regulate uptake and usage across growth stages — a meaningful consideration when running high-light, high-CO2 environments where nutrient demand and metabolic rate are both elevated.

Solubility is addressed at the formulation level: citric acid drives cation uptake and keeps the working solution stable, while the internal surfactant package distributes fertilizer ions evenly through the media and irrigation lines. Consistency in texture can vary batch to batch — from dry powder to a kinetic-sand feel — without any detectable change in EC contribution, so variation in physical appearance is not a quality defect.

The blue dye serves an operational function beyond aesthetics: when Part B dilutes to a clear working-strength solution, it confirms correct dilution has been reached. In high-throughput facilities where multiple tanks run simultaneously, this visual confirmation reduces the risk of under- or over-concentrated deliveries to the canopy.

Dialing It Into Your Facility

Front Row Ag's standard 3:2:2 mixing method calls for two 25 lb bags of Part B dissolved into 50 gallons of stock concentrate — yielding 1 lb per gallon concentration — alongside three bags of Part A and two bags of Bloom, each in their own 50-gallon tank. This configuration allows all three injectors to run at equal injection rates, which simplifies day-to-day dosing and EC validation.

Facilities with fewer injection points can run a 2-doser configuration with Part B and Bloom combined in a single tank. For operations with tighter injection ranges, the 4:3:3 method (three 25 lb bags of Part B into 60 gallons) produces a more concentrated stock that works with equipment requiring lower percentage injection settings. Front Row Ag publishes EC validation charts for both methods — use them to confirm concentration before each run.

Direct-to-reservoir use is also supported: 1 to 9 grams per gallon depending on growth stage and target EC. For stock concentrate injection without DTR, inject at 6 to 36 mL per gallon, adjusted based on lbs-per-gallon concentration in the stock tank. Front Row Ag's online feed calculator is useful for dialing in injection rates by EC target and growth stage across the system.