Emerald Harvest Cali Pro Bloom A – Quart

Emerald Harvest Cali Pro Bloom A is Part A of a complete 2-part base nutrient series designed to feed high-yield indoor crops through the flowering stage. Used together with Cali Pro Bloom B, it delivers the nitrogen, phosphorus, potassium, and chelated micronutrients your plants need to develop strong structure and support a full harvest. This quart-size bottle is practical for small to mid-size grow operations or for growers evaluating the Cali Pro line before committing to larger volumes.

Emerald Harvest Cali Pro Bloom A Specifications

The table below summarizes the key product data sourced from the supplier record and manufacturer documentation for the quart size of Cali Pro Bloom A.

Specification	Value
Product Type	2-Part Base Nutrient, Part A
Series	Emerald Harvest Cali Pro (Bloom A & B)
Volume	1 quart (0.95 L / 946 mL)
Shipped Weight	4.32 lb (1.96 kg)
Primary Macronutrients	Nitrogen, Phosphorus, Potassium
Chelated Micronutrients	Iron, Cobalt, Manganese, Zinc
Application Stage	Flowering (Bloom phase)
Grow Environment	Indoor, high-yield crops
Brand	Emerald Harvest (Hawthorne Garden Company)
Supplier SKU	HGC723910

Why Choose Emerald Harvest Cali Pro Bloom A

Cali Pro is Emerald Harvest’s core 2-part base nutrient line, built around the idea that a grower should be able to dial in feeding programs precisely without relying on complex multi-bottle stacks during the bloom phase. Here is what makes this product worth considering:

• Designed specifically for the flowering stage. Cali Pro Bloom A & B provides the nutrient ratios your crops need during flower development — rich in phosphorus and potassium to support vigorous fruiting and dense bud formation, while still delivering the nitrogen backbone that sustains stalk and stem integrity through the bloom period.
• Chelated micronutrient package. The formula includes chelated iron, cobalt, manganese, and zinc. Chelation keeps micronutrients soluble and available across a wider pH range, reducing the risk of lockout that can stall growth mid-bloom.
• 2-part system for precise control. Splitting base nutrients into an A and a B part allows each bottle to carry concentrated nutrient loads without the precipitation that can occur when certain elements are stored together. You mix both parts per dose for a complete feed, and you adjust the ratio as needed when your plants signal it.
• Part of a matched grow-and-bloom series. Cali Pro Grow A & B and Cali Pro Bloom A & B are formulated as a system. Growers who run both phases through the same brand line get consistent baseline chemistry with a predictable EC ladder from seedling through harvest.
• Quart size for smaller operations or trials. The 1-quart bottle gives small-tent growers and first-time Cali Pro users a manageable entry point. At a 1-quart yield, you get enough concentrate to run a meaningful number of feeding cycles before needing to restock.

Best Uses for Emerald Harvest Cali Pro Bloom A

This product fits a specific position in the grow room: it is the bloom-phase base nutrient for indoor, high-yield crops run on a 2-part system. Below are the scenarios where it fits best.

• Indoor hydroponic reservoirs during flower. Add Cali Pro Bloom A alongside Bloom B to your reservoir at the start of the flowering stage and continue through the end of the bloom cycle. The chelated micronutrients remain available in solution at typical hydroponic pH ranges (5.5–6.5).
• Coco coir and soilless media. Cali Pro’s 2-part format works well in coco coir and other soilless media where growers manage nutrients entirely through irrigation. The phosphorus and potassium levels are appropriate for the heavier bloom-feed demand of coco grows.
• Small-tent and hobby grow rooms. The quart size is practical for 2×2 to 4×4 tent setups where a larger jug would sit unused for extended periods and risk degradation. Buying at quart scale keeps concentrate fresh and reduces waste.
• Pairing with Cali Pro Grow A & B for a full-cycle program. Growers who want a single brand feeding program from vegetative through flower can run Cali Pro Grow A & B in veg, then transition to Bloom A & B when the photoperiod shifts, maintaining consistent base chemistry throughout the lifecycle.
• Supplement programs that require a defined base. If you are running bloom boosters, cal-mag additives, or enzyme products alongside your base, having a clearly defined 2-part base like Cali Pro makes it easier to track EC contributions and isolate which component is driving plant response.

Cali Pro Bloom A vs Similar 2-Part Bloom Base Nutrients

The 2-part base nutrient category includes several well-established options. Cali Pro Bloom A sits alongside products like Advanced Nutrients pH Perfect Sensi Bloom, General Hydroponics Flora Series components, and other split-formula bloom bases. The main differentiators growers cite when comparing these products come down to the micronutrient delivery method, pH buffering behavior, and overall ease of use.

Cali Pro does not include a pH-perfect or auto-buffering chemistry — growers will still need to check and adjust pH with every reservoir change. This is a straightforward approach that some growers prefer because it keeps pH management in their hands rather than relying on a buffering mechanism they cannot see. The chelated micronutrient package (iron, cobalt, manganese, zinc) is designed to minimize lockout in the absence of pH auto-correction.

The 2-part format itself is common across the category. The quart entry price point makes Cali Pro Bloom A competitive for growers who want a well-supported brand-name base nutrient without committing to a gallon or larger volume on first purchase. If you are looking for complementary additives to run alongside a base like this, products such as Advanced Nutrients Tarantula (a microbial inoculant) can be layered into a bloom program to support root health through the fruiting phase, while a rooting solution like Heavy 16 Roots addresses root zone support at a different stage of the cycle.

Compatibility

Cali Pro Bloom A is formulated for indoor high-yield crops in hydroponic, coco coir, and soilless media environments. The following notes are derived from the manufacturer’s product documentation.

• Grow medium compatibility: Hydroponics (recirculating and drain-to-waste), coco coir, and other soilless substrates. Less commonly used in heavy soil mixes, where native soil biology can interact unpredictably with synthetic nutrient solutions.
• Part pairing requirement: Cali Pro Bloom A must be used in combination with Cali Pro Bloom B. Neither part is a standalone complete bloom nutrient — both are needed to provide a full nutrient profile.
• Cali Pro Grow series pairing: The Bloom series is designed to transition directly from the Cali Pro Grow A & B program, maintaining the same brand chemistry across the vegetative-to-flower transition.
• pH range: Target reservoir pH of 5.5–6.5 for hydroponic and coco applications. The chelated micronutrients support availability across this range, but pH should still be monitored and adjusted each feeding.
• Additive compatibility: Compatible with bloom boosters, cal-mag supplements, and enzyme products commonly used in indoor gardens. Always add each product separately to your reservoir, mixing each in before adding the next, to avoid interactions in the concentrate stage. If you are running a biological product like PureCrop1, note that biological and synthetic nutrient products should be added separately and the reservoir checked for any cloudiness or precipitation.

Dosing Guidelines

The following dosing guidance is based on general best practices for 2-part hydroponic base nutrients and the manufacturer’s published usage framework for the Cali Pro line. Always refer to the Emerald Harvest feeding chart (available at hawthornegc.com) for the specific dose rate per gallon for each week of the bloom cycle, as the recommended amount shifts as flowering progresses.

• Shake or stir well before measuring. Liquid concentrates can stratify over time. Invert the bottle several times before drawing a dose to ensure a consistent nutrient ratio.
• Add Bloom A and Bloom B separately to your reservoir. Do not pre-mix the two parts together in concentrate form — add Part A to water first, stir, then add Part B, stir again. This prevents nutrient precipitation in the mixing vessel.
• Start low, adjust based on plant response. For growers new to the Cali Pro line, start at the lower end of the recommended dose range and increase over successive feedings as you observe plant response. Check EC (electrical conductivity) after mixing to verify the solution strength matches your target range for the bloom week.
• Check and adjust pH after mixing. Cali Pro Bloom A does not include a pH-buffering system. Measure pH after adding both parts and any other additives, then adjust to your target range (5.5–6.5 for hydroponics and coco) before delivering to plants.
• Monitor runoff EC and pH. For drain-to-waste and coco systems, monitoring runoff EC and pH gives you an early signal of salt accumulation or pH drift in the root zone. Adjust feeding strength or flush frequency based on runoff readings.

How to Use Cali Pro Bloom A

1. Confirm your crop is in the flowering stage. Transition from your Cali Pro Grow A & B program to Bloom A & B when you switch photoperiod or observe the first signs of flower initiation. Running Bloom nutrients too early can under-supply nitrogen during late vegetative stretch.
2. Shake the Cali Pro Bloom A bottle thoroughly before each use to redistribute any settled particles and ensure the concentrate is uniform.
3. Measure the recommended dose of Bloom A per gallon of water. Use a calibrated syringe or measuring cup. Refer to the Emerald Harvest Cali Pro feeding chart for the dose rate appropriate to the current week of your bloom schedule.
4. Add Bloom A to your reservoir or mixing container filled with fresh water. Stir or circulate to incorporate. Do not add to an already concentrated solution.
5. Measure and add Cali Pro Bloom B separately. Follow the same dose rate. Add to the reservoir after Bloom A is fully mixed in. Stir again.
6. Add any supplemental products (cal-mag, bloom boosters, enzymes) one at a time after both base parts are mixed, stirring between each addition.
7. Test and adjust pH to your target range (5.5–6.5 for hydroponics; 6.0–6.5 for coco) after all additives are incorporated.
8. Verify EC is within your target range for the current bloom week before delivering to plants.
9. Deliver to plants via drip, flood-and-drain, or hand-watering. Discard unused mixed solution rather than storing it — mixed nutrient solutions degrade and can support microbial growth over time.

Sources & Further Reading