Humboldt Nutrients Master A – 1 gal

Humboldt Nutrients Master A is Part A of the Master A&B two-part base fertilizer program — a premium mineral nutrient formula designed for all plants and growing media. Unlike conventional two-part programs, Master A&B uses natural amino acid chelation for all micronutrient content, making it 100% biodegradable and free of the synthetic EDTA and EHDDA chelating agents found in most competing programs.

Humboldt Nutrients Master A Specifications

Key physical and formulation specifications for the Humboldt Nutrients Master A 1-gallon container, as sourced from the canonical product record and manufacturer documentation.

Specification	Value
Brand	Humboldt Nutrients
Product Name	Master A (Part A of Master A&B two-part system)
Container Size	1 gallon (128 fl oz)
Shipping Weight	11.0 lb
Chelation Method	Natural amino acid chelation (no EDTA, no EHDDA)
Biodegradability	100% biodegradable
Formulation Type	Liquid concentrate, mineral-based
Compatible Growing Media	All (hydroponics, coco coir, soil)

Why Choose Humboldt Nutrients Master A

The Master A&B program is Humboldt Nutrients’ answer to a recurring problem in the two-part nutrient market: most synthetic base nutrients rely on EDTA (ethylenediaminetetraacetic acid) and EHDDA to chelate heavy metal micronutrients — meaning to keep them soluble and available to plant roots. These chelating agents are synthetic industrial chemicals. When they accumulate in runoff water or irrigated soil, they resist breakdown and can persist in the environment.

Humboldt Nutrients took a different approach for the Master Series. Every micronutrient in Master A&B is chelated using natural amino acids instead. Amino acid chelates are recognized and processed by soil biology; they break down fully after use. The formulation is described as 100% biodegradable without compromising the nutrient availability or crop performance growers expect from a mineral base program.

The program is also formulated with high-quality mineral ingredients throughout, not a blend of lower-cost inputs. For growers who care about what goes into their growing medium and their runoff, the Master Series offers a mineral-grade performance profile combined with an environmental profile closer to what you’d expect from an organic program.

• Amino acid chelation: All micronutrients are chelated with natural amino acids — no EDTA, no EHDDA. The chelates are fully biodegradable.
• 100% biodegradable formula: Breaks down in soil and water without leaving persistent synthetic residues.
• High-quality mineral ingredients: The Master Series uses premium-grade mineral inputs throughout the formulation, not lower-cost substitutes.
• Designed for all plants and media: Works in hydroponics, coco coir, and soil — growers don’t need separate formulas for different systems.
• Two-part system simplicity: Master A and Master B are used together at equal rates, keeping the feeding program straightforward without sacrificing mineral completeness.

Best Uses for Humboldt Nutrients Master A

Humboldt Nutrients Master A is the Part A component of a complete two-part base nutrient program. It is used together with Master B throughout the entire crop cycle. Below are the situations where this product is well suited.

• Hydroponic systems (DWC, NFT, ebb & flow, aeroponics): The liquid concentrate mixes cleanly into reservoir water. The amino acid-chelated micronutrients remain stable in solution across a broad pH range, which is critical in recirculating systems where micronutrient lockout is a common problem.
• Coco coir growing: Coco has a naturally high cation exchange capacity that can tie up calcium and magnesium. The Master A&B mineral formulation provides the elevated Ca and Mg levels typical of coco-specific programs, without requiring separate coco supplements for growers following the standard mixing rate.
• Soil and soilless media: Growers using amended potting mixes or peat-based media can use Master A&B as a complete mineral base, relying on the amino acid chelation to work alongside soil biology rather than against it.
• Environmentally conscious operations: Grows where runoff quality matters — greenhouse operations near waterways, farms under discharge regulations, or growers committed to sustainable inputs — benefit from a base nutrient whose chelation chemistry breaks down in the environment rather than persisting.
• Complementing biological amendments: Because the chelation system is compatible with soil biology, Master A&B works alongside microbial inoculants and organic amendments. Pair it with a root inoculant like Advanced Nutrients Tarantula or a humic supplement for a more complete feeding program.

Humboldt Nutrients Master A vs Similar Two-Part Programs

Most two-part and three-part synthetic base nutrient programs on the market use EDTA or EHDDA chelating agents to keep heavy metal micronutrients (iron, manganese, zinc, copper, boron, molybdenum) in solution. These agents work — micronutrients remain available to plant roots — but the chemistry has a drawback: EDTA and EHDDA are persistent organic pollutants. They do not break down readily in soil or water, and their long-term accumulation in irrigated soils and downstream waterways is a documented environmental concern.

The Humboldt Nutrients Master Series replaces synthetic chelates entirely with natural amino acids. Amino acid-chelated micronutrients are absorbed by plants through the same pathways as amino acid-chelated minerals found in organic inputs. After use, the chelating molecules break down through normal biological activity rather than accumulating. The trade-off traditional growers expect — that going "more organic" means lower efficacy — is what Humboldt addresses directly: the mineral nutrient content and crop performance of Master A&B are designed to match or exceed what EDTA-based programs deliver.

For growers comparing the Master Series to programs like General Hydroponics Flora Series or similar three-part systems, the primary practical differences are: (1) Master A&B is a two-part system rather than three-part, which simplifies mixing; (2) the chelation chemistry is biodegradable; and (3) the formulation is designed for all growing media without a separate coco or soil variant.

Compatibility

Humboldt Nutrients Master A is the Part A component and must always be used in combination with Humboldt Nutrients Master B. Do not attempt to use Part A alone as a complete base nutrient — the two parts are formulated to complement each other and together provide a full mineral profile.

Growing media compatibility: The Master A&B program is designed for all growing media — hydroponics, coco coir, peat-based soilless mixes, and amended soil. No media-specific variant is required.

Supplemental compatibility: Master A&B functions as a base nutrient and is intended to be used alongside Humboldt Nutrients’ supplemental line (bloom boosters, root additives, finishers). It is also compatible with third-party supplements, pH adjusters, and beneficial microbial products. When adding other nutrient concentrates to a reservoir, always add Master A and Master B separately to the reservoir before combining with other concentrates — never pre-mix the two parts in an undiluted state, as this can cause nutrient precipitation.

Water quality: Works with RO water, tap water, and well water. When starting with RO or low-EC source water, follow the manufacturer’s recommended base feeding rate and adjust upward if the crop shows signs of underfed growth. For growers managing a complete nutrient program, consider pairing with a carbohydrate supplement to support microbial activity in the root zone alongside this mineral base.

Dosing Guidelines

Specific per-gallon dose rates for Humboldt Nutrients Master A are published in the Master Series feed chart available on the manufacturer’s website. The guidelines below reflect standard practices for two-part liquid base nutrients; consult the official Humboldt Nutrients feed chart for confirmed ml/gallon rates by growth stage.

General mixing approach:

1. Start with your source water at room temperature. If using tap water, let it sit 24 hours or use a dechlorinating agent before mixing nutrients.
2. Add Master A to the reservoir or mixing container first, at the manufacturer’s recommended rate. Stir or agitate to incorporate fully before proceeding.
3. Add Master B at the same rate as Master A. The two parts are used at equal volumes. Do not add them simultaneously to undiluted water — always dilute each part into the full water volume before adding the other.
4. After adding both parts, check and adjust pH to the target range for your growing media: 5.5–6.2 for hydroponics and coco; 6.0–6.8 for soil.
5. Measure EC (electrical conductivity) with a calibrated meter. Compare to the target EC for the crop’s current growth stage. Adjust the dose rate up or down in subsequent feedings based on plant response and runoff EC.
6. Use fresh mixed solution within 24–48 hours for best results in recirculating systems. Reservoir change frequency depends on system type and crop size.

For growers new to two-part programs, starting at 70–80% of the recommended rate and building toward full strength over the first week reduces the risk of nutrient burn on transplants and young seedlings. Established vegetative and flowering plants typically run at full recommended rates.

How to Mix Master A Into Your Feed Program

1. Obtain the Humboldt Nutrients Master Series feed chart from the manufacturer’s website (humboldtnutrients.com). This chart specifies ml/gallon rates for each growth stage and lists any recommended supplements.
2. Measure out Master A using a calibrated syringe or measuring cup. Use clean, dedicated measuring tools — cross-contamination between concentrated nutrient parts can cause precipitation in the measuring vessel.
3. Add Master A to the bulk of your water volume first. For a 5-gallon reservoir, fill to approximately 4.5 gallons, add and stir Master A, then add Master B, then top off to volume.
4. Add Master B at the same volume as Master A. Stir thoroughly. The solution should be clear to slightly tinted with no visible precipitate. If cloudiness appears, check water temperature and source water hardness; precipitate can form in very hard or cold water.
5. Adjust pH after adding all nutrients. Use a calibrated pH meter, not strips. Target 5.5–6.2 for hydroponics/coco, 6.0–6.8 for soil.
6. Verify EC. A calibrated EC or TDS meter confirms you’re in the right concentration range for the growth stage. Compare to the feed chart’s target EC column.
7. Add any supplements (root enhancers, bloom boosters, pH buffers) after the base nutrients are fully mixed and the EC has been checked. Always add supplements to the diluted solution, not to concentrates.
8. Label your reservoir with the mix date and EC reading. Monitor EC daily in recirculating systems and top off with plain pH-adjusted water when EC rises between feedings.

If you’re running a complete Humboldt program, a root inoculant like PureCrop1 can be used alongside Master A&B to support plant health throughout the grow cycle.

Sources & Further Reading