Plagron - Hydro Roots

A mineral fertiliser with 20.47% phosphorus and 0.02% boron, registered as NPK 0-20-0. Developed for plant roots in hydroponic systems, 1 ml per litre at every watering.

This is phosphate, and it helps to know that

On the shelf this sits among the root stimulators. In its registration it is something else: NPK 0-20-0. No nitrogen, no potassium, a little over twenty percent phosphorus.

That is not a criticism of the product but the point of it. A young root system needs phosphate, and more of it per gram of plant than at any later moment. Phosphate sits in the cell's energy transport and in cell division itself, and cell division is exactly what a growing root tip does all day. Plagron give the same account: phosphorus promotes root growth, increases root length, and improves both root cell division and root cell enlargement.

What it does not do is prompt the plant into anything. There are no vitamins, hormones or amino acids in it acting on the plant's own processes. It supplies the building block most in demand in that phase, and nothing else. That makes it predictable, and it also makes clear when it adds nothing: if your base feed already supplies plenty of phosphate, you are buying more of something you had enough of.

The 0.02% boron is not incidental

Alongside the phosphate one trace element is declared: boron, at 0.02%. A small figure with a specific reason.

Plagron give that reason themselves: boron increases the activity of enzymatic systems, which results in better nutrient absorption. Underneath that sits boron's role in building cell walls and in cell division at growing points. A root tip is such a point, and it is tissue that is constantly extending.

Boron also moves poorly within the plant, so a shortage appears in the youngest tissue and does not recover there. A small, constant supply is therefore more effective than a correction after the fact, and that is precisely what 0.02% at every watering provides.

Why this is for hydro and Power Roots is not

Plagron sell this alongside the organic Power Roots, and the split is functional. They put it this way themselves: Power Roots contains organic components and is therefore less suited to an irrigation system, while Hydro Roots is strictly mineral and causes no problems in a recirculating one.

Behind that difference sits the fact that organic material in water has to be broken down by soil life. In a recirculating system there is no soil life, and the material drifts about causing cloudiness, deposits and blocked drippers. A purely mineral fertiliser has no such problem: everything is already in available form, nothing is left to decompose, and the nutrient solution also stays stable for longer.

Put shortly: hand feeding works with either, feeding a system is what this one is for.

In use

Shake well before use. Mix 1 ml per litre of water, which is 1 in 1000, and feed it at every watering.

On the end date Plagron are not consistent with themselves, which is worth saying. Their product information gives: until the fourth week of flowering for short cycle plants. Their own FAQ gives: stop after the third week of flowering, because from that point the plant is better off putting its energy into flowers than into roots. If you want to avoid the discrepancy, stop at the third week and you are inside both.

Available sizes

Technical Specifications:

• Type: mineral NPK fertiliser (0-20-0)
• Manufacturer: Plagron
• Phosphorus (P): 20.47%
• Boron (B): 0.02%
• Dose: 1 ml per litre of water (1 in 1000)
• Frequency: at every watering
• Period: Plagron give the fourth week of flowering on the product information and the third in their FAQ
• Intended for: hydroponics and inert systems
• Before use: shake well

Frequently asked questions

Is this a root stimulator?
It sits among them, but it is registered as mineral fertiliser 0-20-0. It supplies phosphate, which a young root system wants a lot of, and does not act on the plant's processes.

Do I need it alongside my base feed?
Only if that supplies little phosphate in the early phase. If your base already provides plenty, you are buying more of what you had.

Why is there boron in it?
Plagron cite increased activity of enzymatic systems and so better nutrient absorption. In the plant, boron has a role in cell division and cell wall building at growing points, and a root tip is one.

Why not the organic Power Roots in hydro?
It contains organic components that cause cloudiness and blockages in a system. Plagron advise against it there themselves and point to this one.

How long do I feed it?
Plagron name two moments: the fourth week of flowering on the product information, the third in their FAQ. Stop at the third and you are inside both.