Grotek Monster Bloom is a water-soluble powdered bloom enhancer from Grotek, a Hydrofarm brand. It supplies phosphorus and potassium only, with no nitrogen, and is added to a complete base nutrient during the flowering stage. Grotek calls it its classic bloom enhancer and lists its key benefits as larger flower clusters, improved harvest yield and support for the ripening stage.
Key Facts About Grotek Monster Bloom
- Guaranteed analysis on Grotek’s product page: 50% available phosphoric acid (P₂O₅) and 30% soluble potash (K₂O), with no nitrogen listed. That is an NPK ratio of 0-50-30.
- A single source material: monopotassium phosphate (MKP). No other ingredient is declared on the label.
- Grotek describes it as supporting protein and starch synthesis, stalk and stem strength, the movement of sugars and starches within the plant, and respiration and CO₂ uptake during bud development.
- Mixing rate: 1 teaspoon per 5 US gallons of water (6 g per 19 L) for soil, soilless and water culture, with every fertilizer application during flowering.
- Start when buds are forming and stop 1-2 weeks before harvest.
- Grotek lists hydroponics and soilless media (peat and coco) as compatible systems.
- Available in 130 g, 500 g, 2.5 kg, 5 kg and 10 kg packs.
Before Adding It to Your Feed
- It is a supplement, not a complete feed. Nitrogen, calcium, magnesium and the micronutrients still have to come from the base nutrient.
- Check the EC and pH of the final solution after adding it. Too much phosphorus and potassium raises the EC of the root zone and can burn leaf tips.
- Do not combine it with a second PK booster without reading both labels, or the phosphorus and potassium dose doubles.
For the conversion from oxide to elemental phosphorus and potassium, what these two nutrients do during flowering, and the most common mistakes, see the full Monster Bloom guide.
Documentation and Support
AZ Growshop is an authorized Grotek distributor for Thailand. We supply Monster Bloom in the manufacturer’s original sealed packaging with its certificate of analysis (COA) and safety data sheet (SDS), and offer technical support for farms working toward GACP standards.