Soil vs Coco vs Hydro: Choosing Your Growing Medium (Biobizz Soil, Canna Soil & Coco Compared)

Soil is the most forgiving medium and the best choice for beginners — it buffers feeding and watering mistakes, and pre-fertilised Biobizz soil or Canna soil can carry young plants for weeks. Coco coir grows faster but is inert, dries out quicker and needs Cal‑Mag plus more frequent feeding. Hydroponics gives the fastest growth and highest yields but is the least forgiving of any mistake.

That is the short version. Biobizz soil is a range of organic, pre‑fertilised potting mixes (Light‑Mix and All‑Mix); Canna soil — sold as Canna Terra — is a peat‑and‑perlite potting range. Below we compare the three media side by side, explain where Biobizz Light‑Mix, Biobizz All‑Mix and Canna Terra sit, and cover the one thing that trips up most coco beginners: buffering and the Cal‑Mag link. Everything here is written for UK home growers, with UK water, UK delivery and practical advice from our Peterborough shop floor.

Soil vs coco vs hydro: what is the difference?

This is the table to bookmark. "Forgiveness" means how much room the medium gives you to make a watering or feeding mistake and still recover.

Two honest caveats the Reddit and US blog comparisons often skip. First, soil being "slow" is a feature for beginners, not a flaw — the slow nutrient release is exactly what forgives a missed feed. Second, coco is technically a soilless / hydroponic substrate, so a lot of "is coco hydro?" confusion is just terminology (more on that below).

Light Mix vs All Mix: which soil should you choose?

Soil is the classic UK starting point. A good potting soil already contains organic matter and a starter charge of nutrients, so it feeds the plant for the first weeks and cushions pH and watering errors. The two big brands we sell from the Peterborough store are Biobizz (soil) and Canna (soil), and the choice between Biobizz Light‑Mix and All‑Mix is the one most new growers get stuck on.

• Biobizz Light‑Mix 50L — a lightly pre‑fertilised, well‑draining mix with a medium EC. It holds only a small starter charge, so you start liquid feeding sooner (within a week or two). That sounds like more work, but it gives you precise control and makes Light‑Mix the safer pick if you tend to over‑feed, or if you run automatic irrigation that needs good drainage.
• Biobizz All‑Mix 50L — a richer, pre‑fertilised "outdoor‑style" soil designed to fuel vigorous growth for several weeks with no extra feed. Less day‑one effort, but the heavier charge is easier to over‑do with seedlings, which is why many growers pot seedlings into Light‑Mix and step up to All‑Mix later.

The Canna soil equivalent

The Canna soil equivalent is Canna Terra Professional 50L — a high‑nitrogen peat‑and‑perlite potting soil with a light starter charge, sitting closest to Light‑Mix in philosophy. There is also a richer Canna Terra Professional Plus (pH‑adjusted with a full‑cycle lime charge), which behaves more like All‑Mix. Match your nutrient line to your soil — see our nutrient‑line‑by‑medium guide.

A quick rule of thumb: Light‑Mix or Canna Terra Professional for control and seedlings; All‑Mix or Terra Professional Plus for a richer, lower‑effort start.

How do you use coco coir, and why does it change how you feed?

Coco coir looks like soil and waters like soil, but it behaves like hydroponics — and that is the single most important thing to understand before you switch. Browse the full Coco collection and you will see "buffered" and "RHP‑certified" on the good bags. Here is why those words matter.

Coco is inert. It holds almost no nutrients of its own, so unlike soil there is no buffer to forgive a skipped feed — you provide a complete, balanced feed from day one.

Coco has a high cation exchange capacity (CEC). Its binding sites naturally arrive loaded with potassium and sodium. When your nutrient solution hits fresh coco, those sites swap: they grab calcium and magnesium out of your feed and release potassium back. The practical result is that coco strips Ca and Mg from your solution until those sites are saturated — which shows up as a calcium/magnesium deficiency on new growth.

This is what "buffering" fixes. Buffering means soaking the coco in a calcium‑magnesium solution before use, so Ca/Mg lock onto the freed‑up sites and stay put. Quality coco like Canna Coco or Gold Label arrives pre‑buffered and RHP‑certified, which saves you the job. But — and this catches people out — even with pre‑buffered coco you should still add Cal‑Mag to your irrigation water throughout the grow, especially in the UK if you use RO or soft water that carries little dissolved calcium to begin with. We cover dosing in our dedicated coco & Cal‑Mag guide.

Watering frequency is higher. Coco holds a high water‑to‑air ratio yet drains and dries faster than soil, so you cannot let it dry out the way you can a soil pot. Expect to water daily, and up to twice a day in peak flower, in small amounts until you see a little run‑off. That faster wet‑dry turnover and constant fresh feed is exactly why coco can outpace soil — but it asks for daily attention. Solid UK options include Canna Coco Professional Plus 50L and Gold Label 60/40 Coco/Clay Pebbles.

What is hydroponics?

True hydroponics removes the substrate almost entirely: roots grow in or are fed directly by a recirculating nutrient solution. Common systems include DWC (deep water culture), NFT (nutrient film technique), drip and aeroponics. Done well, it delivers the fastest growth and the highest yields because the plant gets oxygen and a perfectly tuned feed on demand — nothing held back by a medium.

The trade‑off is forgiveness: there is no soil buffer at all, so a pH swing, a pump failure or an EC mistake can stress plants within hours rather than days. It also needs more kit and tighter daily monitoring. We will cover choosing and running a system properly in a later guide — this post is about choosing your medium, so we will keep hydro at the headline level here.

Is coco better than soil, and which should a beginner choose?

Honest answer: coco is not simply "better" — it grows faster and can yield more, but soil is more forgiving, so for most first‑time UK growers soil is the better choice. Start in soil. The decision logic is simple.

• Choose soil if this is your first grow, your schedule is unpredictable, or you want the medium to forgive the odd missed watering or feed. Biobizz Light‑Mix or Canna Terra Professional are the easiest starting points; All‑Mix if you want a richer, lower‑effort base. This is the right answer for the large majority of UK home growers.
• Choose coco for your second grow, or your first if you can commit to checking and watering daily and you are happy to learn pH/EC and add Cal‑Mag. The reward is faster growth and bigger yields. Pre‑buffered, RHP‑certified coco makes the learning curve far gentler.
• Choose hydro once you are comfortable managing pH and EC and want to push for maximum speed and yield, accepting that it is the least forgiving of mistakes.

There is no single "best" medium — only the best match for your experience and how much daily attention you can give. If you are unsure, soil first, then graduate to coco, then hydro.

Frequently asked questions

Is soil better than coco? For beginners, usually yes — soil is more forgiving because its organic matter buffers pH, nutrient and watering mistakes, and pre‑fertilised mixes feed young plants for weeks. Coco grows faster and can yield more, but it is inert, needs Cal‑Mag and a full feed from day one, and demands daily watering. "Better" depends on how much daily attention you can give.

Is coco considered hydro? Yes — coco coir is a soilless substrate and is classed as a form of hydroponic growing. It is inert and you supply all the nutrients, exactly like hydro. The difference is that coco is hand‑ or drip‑watered in pots rather than sitting in a recirculating reservoir, so it feels more like soil to work with.

What are the downsides of coco? Three main ones: it is inert so there is no nutrient buffer to forgive a missed feed; its high cation exchange capacity strips calcium and magnesium, so you must use pre‑buffered coco and still add Cal‑Mag; and it dries out faster than soil, needing watering up to twice a day in flower. None are dealbreakers — they just mean more frequent, more precise attention.

Do I need Cal‑Mag in pre‑buffered coco? Yes. Pre‑buffering saturates the coco's binding sites so it does not strip your first feeds, but the plant still needs ongoing calcium and magnesium — particularly in the UK with RO or soft water, which carries little to begin with. Add Cal‑Mag to your irrigation water throughout the grow.

How often do I water coco vs soil? Soil: roughly every 2–3 days, watering thoroughly until you see light run‑off. Coco: daily, and up to twice a day in peak flowering, in smaller amounts so a little water reaches the tray. Coco drains and dries faster, so it cannot be left as long as soil.

Is Biobizz Light‑Mix or All‑Mix better for beginners? For most beginners, Biobizz Light‑Mix 50L is the safer pick: it holds only a light starter charge, so you get more feeding control and far less risk of burning tender seedlings. Choose Biobizz All‑Mix 50L if you want a richer, lower‑effort start that feeds vigorous plants for weeks with no extra liquid — just keep it away from young seedlings, which the heavier charge can overwhelm.

What is the Canna equivalent of Biobizz soil? Canna's soil range is sold as Canna Terra. Canna Terra Professional 50L is the close equivalent of Biobizz Light‑Mix (a light starter charge for control and seedlings), while Canna Terra Professional Plus, with its fuller lime‑and‑nutrient charge, behaves more like All‑Mix for a richer, lower‑effort start.

Products and where to start

Everything here is in stock at our Peterborough store and online, with free UK mainland delivery over £50 (exclusions apply — check the basket).

• Biobizz Light‑Mix 50L — lightly fertilised, well‑draining soil; best beginner soil for control.
• Biobizz All‑Mix 50L — richer pre‑fertilised soil for a lower‑effort start.
• Canna Terra Professional 50L — high‑nitrogen Canna soil, the Light‑Mix equivalent.
• Canna Coco Professional Plus 50L — pre‑buffered, RHP‑certified coco.
• Gold Label growing media — including 60/40 coco/clay‑pebble mixes.
• Most relevant collection: browse all substrates in the Growing Media collection.

Related reading: Matching your nutrient line to your medium · Coco coir and the Cal‑Mag link, explained.

Why trust The Grow Superstore

The Grow Superstore has been supplying UK indoor and hydroponic growers since 2009, from our shop at 6 Wulfric Square, Bretton, Peterborough. We stock and use these media every day, so the advice above comes from real shop‑floor experience, not just spec sheets. Pop in for a free in‑store consultation, or message the team and we will help you pick the right medium for your space, your water and your experience level. Free UK mainland delivery on orders over £50.