Coco Nutrients

Why coco coir needs its own nutrient

Coco coir is not inert the way clay balls or rockwool are. The fibre carries an exchange capacity that holds onto calcium and magnesium from your feed and gives up potassium in return, which is why a nutrient built for a bare reservoir runs plants short in coco. Growth Technology states its coco mineral profile “compensates for the tendency of coco fibre to lock up available calcium”; Plant Mechanics warns that coco “tends to bind calcium and magnesium”.

More calcium and magnesium, less potassium

Hy-Gen builds additional calcium into CocoGrow, noting that calcium is what commercial cocopeat buffering already uses. Advanced Nutrients adds bioavailable calcium, magnesium and multiple forms of chelated iron to Sensi Coco to head off lockout. House & Garden goes the other way on potassium, running Cocos A&B slightly lower “to account for the K organically released from coco coir decomposition”.

Chelates that keep trace elements available

Growth Technology adds fulvic acid, Nutrifield adds fulvic acid and suspended silica, and Canna uses natural chelates — all to keep minerals available in a medium that ties them up.

Why coco base nutrients come as A and B

Because the elements cannot share a concentrated bottle. Canna is explicit: some elements in parts A and B “clog together” if combined at full strength, leaving nutrients the plant cannot absorb, so you add A to the water first, stir, then add B. House & Garden warns the same mix causes parts of the nutrient to solidify, and Growth Technology adds that A and B must go in at equal rates. Two bottles is chemistry, not marketing.

Our range of coco nutrients

Two-part coco base feeds

The core of the collection. Canna Coco A & B comes in 1L, 5L and 20L and deliberately has no separate veg and flower version — one formulation covers both stages. House & Garden Cocos A&B runs 1L through to 20L, Plant Mechanics Coco+ A&B covers 1L, 5L and 20L, and Reiziger Coco Food A+B, Nutrifield Coco A&B and Dutchfest Coco A&B fill in the 1L and 5L sizes.

Stage-split grow and bloom sets

Growth Technology splits its range into Coco Grow A&B and Coco Bloom A&B, both in 1L, 5L and 20L. Hy-Gen does the same with CocoGrow and CocoBloom, and recommends running CocoGrow into early flower before handing over. Alongside these sit starter kits — House & Garden's Coco kit, the ISN Starter Pack and the Professor's Growers Kits — pairing a base feed with that brand's additives.

How to choose a coco nutrient

1. Decide one formula or two. A single formulation such as Canna Coco or Plant Mechanics Coco+ runs start to finish. A split grow and bloom set gives you more control over the flip into flower, but is more to manage.
2. Check what calcium and magnesium is already in there. Coco-specific feeds carry more than a hydroponic equivalent. If yours does not say so, or you are on rainwater or RO, budget for a cal-mag supplement on top.
3. Buy the size that matches your run. A&B sets are sold as a pair, so a 5L listing means 5L of A and 5L of B. One-litre bottles suit a single tent; 20L drums feed a room.
4. Buffer and rinse the coco first. Plant Mechanics advises pre-washed, buffered coco; Growth Technology says flush new coco before planting. The best nutrient will not rescue unbuffered coir.
5. Set pH and EC for coco, not for hydro. Plant Mechanics calls for pH 5.8–6.3; Growth Technology says aim for 6 and lift EC gradually through veg, from around 1.2mS to 1.6mS.

Feeding coco day to day

Coco is run wet and often. Plant Mechanics recommends frequent watering with 10–20% runoff so salts do not accumulate, with controlled dry backs for root oxygenation. Growth Technology warns that coco holds far more water than growers expect and that systems need flushing at least weekly. It suits run-to-waste and passive systems, not a recirculating reservoir.

If the leaves say something is off, our guide to yellow leaves and common grow problems is the place to start, and the cal-mag supplements range covers the top-up when a base feed is short.