Nutrients — Roots

A root stimulator is bought for a window, not for a whole cycle. Everything on this page works in the first weeks after cutting, sowing or transplanting, and the real question is which type suits the way you grow.

The window is narrow

The gain sits in the weeks while the root system is still the limit on everything downstream. Once the pot is rooted through, that limit has moved to light and feed, and carrying on stimulating buys little. So start straight after cutting or transplanting and reckon on about three weeks. Buy one halfway through bloom and you are paying for work that is already done.

Plant extract or live bacteria

Two different things sit side by side here. Extract-based stimulators push the plant into building more root itself: CANNA Rhizotonic and the organic Biocanna Bio Rhizotonic, Atami Ata Rootbastic, Ata Rootfast and B'cuzz Root Stimulator, Bio G Power Wortel Max and Plagron Power Roots. Alongside them is No Mercy Supply Bacterial, which puts live culture into the root zone.

That difference has one practical consequence. A live culture and anything from System Cleaning do not belong in the same tank: a cleaner is there to clear organic material and draws no distinction between fouling and what you have just added. Flush the system first, then introduce the culture.

Split by substrate

Hy-pro is the only brand here that sells its Rootstimulator per substrate, in a terra, coco and hydro version. Plagron puts a separate Hydro Roots next to Power Roots. On coco or in a system that is the easiest choice, because the dose is already matched to your medium.

Frequently asked questions

When do I stop using a root stimulator?
Once the pot is rooted through, usually somewhere in the third or fourth week. Some feed charts bring it back around the flip; that is the manufacturer's call and it will be written into that chart.

Do I need one if I already run a complete line?
Not strictly, because a complete line supplies every element. Of all the add-ons this is the one that most often pays for itself, precisely because it acts while the plant still has the most to gain.

Can I combine two root products?
An extract and a live culture do not fight each other. Two extracts from different brands do the same job, so you are paying twice. Pick one and stay on it through the whole start period.