Growth Technology Optimum Bloom A & B | 2-Part Flowering Nutrient | 2x1L, 2x5.5L, 2x20L

Australia’s Original Hydroponic Nutrient — Still the Best at Flower

Growth Technology Optimum Bloom A & B is one of Australia’s first and most trusted hydroponic nutrient solutions — an industry standard that’s been delivering exceptional flowering results for decades. Formulated to the highest standard of accuracy from the purest, most soluble mineral salts, it gives your plants everything they need during the flowering and fruiting stage in a complete, balanced, chelated 2-part formula.

Why Growth Technology Optimum Bloom Is an Australian Classic

• 🌸 Precision mineral formulation — calculated to the highest possible standard of accuracy for consistent, reliable results every cycle
• 🌸 Purest, most soluble mineral salts — clean mixing, no sludge, no residue in your system
• 🌸 Chelated micronutrients — remain available to the plant even during pH fluctuations, so nothing is wasted
• 🌸 Reduced nitrogen, elevated P&K — the bloom-stage ratio that drives bud initiation, flower development, and fruit set
• 🌸 Suits all hydroponic systems — especially recommended for NFT, flood & drain, and recirculating systems with perlite or clay
• 🌸 Trusted by Australian growers for decades — the benchmark that other nutrients are measured against

How to Mix & Use Optimum Bloom

1. Fill your reservoir with fresh water
2. Add Optimum Bloom A at 4ml per litre and stir thoroughly
3. Add Optimum Bloom B at 4ml per litre and stir thoroughly
4. If using additives, add them before final pH adjustment
5. Adjust pH to between 6.0 and 6.5

⚠️ Always add A and B in equal parts. Never mix A and B together undiluted.

Target EC: 2.0–2.5 mS/cm during flowering. Start at the lower end and increase as plants develop. Change recirculating reservoir weekly to maintain an optimal mineral profile.

Important Tips

• Gradually increase EC through the flowering cycle — don’t jump straight to maximum strength
• Never ignore pH — minerals become inaccessible outside the 6.0–6.5 range; check every feed
• Change your reservoir weekly in recirculating systems to prevent mineral imbalance build-up
• Add additives before adjusting pH — always do your final pH check after everything is in the tank

Optimum Bloom vs Optimum Grow

Optimum Bloom is formulated with reduced nitrogen and elevated phosphorus and potassium for bud initiation, flower development, and fruit set. Coming out of veg? Switch from Growth Technology Optimum Grow A & B — which is high in nitrate-nitrogen for rapid vegetative development — to Optimum Bloom as soon as your plants begin to flower.

Get Even More From Your Bloom

• GT Super PK — adds concentrated P&K for heavier, denser flowers and better quality at harvest
• GT Silica — strengthens cell walls for more resilient plants through the stress of late-stage flowering
• GT Fulvic — enhances nutrient uptake and adds an organic component to your mineral programme

Choose the Right Size

• 2x1L — ideal for home growers and small flowering systems
• 2x5.5L — great value for regular growers running multiple flowering cycles
• 2x20L — best value for large-scale grows and commercial flowering operations

By Growth Technology — proudly Australian, trusted by hydroponic growers nationwide for decades.