What is Professor’s Nutrients Grow Fast and what does it do?
Grow Fast is a nitrogen-rich veg booster designed to accelerate leafy growth, stem development, and canopy size during the vegetative stage. It’s an additive used alongside your base nutrients, not a complete feed.
When should I use Grow Fast—and when should I stop?
Start using Grow Fast from the second week of veg once plants are feeding well. Stop at the first signs of flowering or when you flip to a bloom light cycle. It’s not recommended during flower due to its nitrogen content.
How much Grow Fast should I use in soil, coco, or hydro?
Use 2 mL/L in soil, 2–2.5 mL/L in coco, and up to 2.5 mL/L in hydro. Start at half-strength if you’re unsure how your plants will respond, and increase gradually. Watch total EC to avoid overfeeding.
What’s the best way to mix Grow Fast with my nutrients?
Always mix nutrients one at a time. Add base nutrients to water first, then Grow Fast, then mix thoroughly. Adjust pH last. Never mix concentrates directly together in the same container.
Will Grow Fast affect pH or EC?
Yes—it raises EC and can slightly affect pH depending on your water. Always check and adjust pH after mixing all nutrients. Monitor EC if you're working with sensitive or young plants.
Can I use Grow Fast with other nutrient brands or additives?
Yes—Grow Fast is compatible with most nutrient lines, including A+B bases, Cal-Mag, enzymes, root stimulants, and silica. Just keep your total EC in check and avoid stacking too many strong products at once.
What systems is Grow Fast compatible with?
Grow Fast works in hydroponics, coco coir, soil, DWC, and drain-to-waste systems. In recirculating hydro, keep reservoirs clean, well-aerated, and monitor water temps to prevent buildup or nutrient issues.
Can Grow Fast reduce veg time or increase yield?
Yes—faster, healthier growth in veg can lead to a shorter cycle and more productive plants in flower. While it won’t guarantee bigger yields alone, it supports the strong foundation needed for higher potential.
Does Grow Fast help with weak growth or pale leaves?
If the issue is nitrogen deficiency, Grow Fast can help. It promotes stronger stems, bushier growth, and improved leaf color. But if the cause is poor lighting, pH imbalance, or root stress, address those first.
What are signs I’m overusing Grow Fast?
Watch for dark green clawing leaves, tip burn, slow uptake, or overly lush growth. These are signs your nitrogen levels or total EC are too high. Back off the dose and simplify your nutrient stack.
Should I reduce base nutrients when using Grow Fast?
Often yes. If your EC target is fixed, you’ll need to lower base nutrient strength slightly to make room for Grow Fast in the mix. Always monitor runoff and plant response.
Can I use Grow Fast with RO or hard tap water?
Yes. Just be aware that hard water already contributes minerals, so adjust your EC targets accordingly. With RO, make sure your base nutrients or additives include calcium and magnesium support.
Is Grow Fast suitable for edible plants like tomatoes or chillies?
Yes—it’s safe for vegetative stages of edible plants. Just avoid overfeeding with nitrogen as fruiting approaches, and follow standard safety practices when feeding food crops.
Can I foliar spray Grow Fast?
It’s not recommended. Grow Fast is designed for root-zone feeding. Foliar application can easily cause spotting or leaf stress due to its strong nitrogen content.
Does Grow Fast stain or have a smell?
It can stain surfaces if spilled and has a typical nutrient smell. Always shake before use, and store sealed in a cool, dark place. Avoid freezing or overheating the product.
