Which Potting Soil? Biobizz, Canna Terra, Plagron and Gold Label

There is no single best potting soil for indoor plants: the big choice is how much food you want already in the bag. A light mix leaves the feeding to you; a pre-fertilised mix feeds the plant for its first few weeks. This guide compares the eight premium soils we sell, as their product pages describe them: what is in each, when to start feeding, and which to pick for seedlings, final pots or an Autopot.

Light mix or pre-fertilised?

A light mix such as Biobizz Light Mix gives you, in its page's words, complete control of the nutritional schedule. A rich mix such as Biobizz All Mix or Plagron Batmix Soil does the early feeding, but growers using mineral feeds must then judge when the plants need more, the Light Mix page notes. With a fertilised soil, the Canna Terra nutrient page says to allow for the food already in the bag when you mix a feed: less is more.

The eight soils compared

The soils we sell, as their product pages describe them. A dash means the page does not say.
Soil	Made from	Food in the bag	Start feeding
Biobizz Light Mix	Peat moss, sphagnum peat, perlite	Light	Once plants are established
Biobizz All Mix	As Light Mix, plus worm castings, mycorrhizae, Pre-Mix	Medium to heavy: the first 2-4 weeks	Low-level organic feed from day one; mineral feed usually from around week 3 or 4
Plagron Lightmix Soil	Peats, fibres, perlite	Kept to a minimum; needs a soil nutrient	–
Plagron Batmix Soil	Premium-soil base plus bat guano	Around 3-4 weeks of rapid growth	After around 3-4 weeks on tap water
Canna Terra Professional	Black peat, granulated peat moss, perlite	Nitrogen-rich	–
Canna Terra Professional Plus	White peat moss, tree bark	Little, apart from trace elements	The first week or two of veg
Gold Label Special Mix Gold	Swedish white peat, perlite, coco coir	Pre-fertilised: NPK 12-12-24, EC 1.5	After around 2-4 weeks
Jiffy Pro7 All+ Mix	Organic materials, beneficial bacteria	–	–

Both Biobizz soils, Plagron Lightmix and the Jiffy come in 50 L bags, the Gold Label in 45 L; the other pages give no size. Both Canna Terras and both Plagrons ship to mainland UK addresses only. The Gold Label page also gives pH 5.8 and suggests adding a root stimulant and a beneficial bacteria or mycorrhizal product (see our root stimulants guide). For the Jiffy, ask us before you plan a feed around it.

Biobizz All Mix vs Light Mix

The All Mix page says the main difference is worm castings and Biobizz Pre-Mix. Our Biobizz feed chart has one schedule for Light Mix and a lighter one for All Mix.

Two tips from the All Mix page: pre-wet the soil in its pots 24-48 hours before potting up, to activate the Pre-Mix, and establish young plants in Light Mix in 1 or 2 litre pots before potting on into All Mix. Before adding more castings or Pre-Mix, read our soil amendments guide.

Canna Terra Professional vs Professional Plus

The names suggest Plus is the richer soil; the pages say the opposite. Canna Terra Professional is black peat, granulated peat moss and perlite: nitrogen-rich, pH-adjusted, good at holding water, and ideal for beginners and professionals, indoors or out, its page says.

Canna Terra Professional Plus is white peat moss and tree bark, with little nutrient apart from trace elements and a lime charge for a whole growth cycle. It is for experienced growers who take over the feeding from the first week or two of vegetative growth. Its starter charge is primed for Canna Terra nutrients (see our Canna Terra feed chart), and the page suggests Biobizz feeds for organic growers.

Plagron Batmix vs Lightmix

Batmix is the usual premium-soil mix plus bat guano, with enough fertiliser for around 3-4 weeks of rapid growth on tap water alone, its page says. It works with Plagron or Biobizz feeds.

Plagron Lightmix keeps its nutrient content to a minimum, so you will need a soil nutrient such as Hesi TNT Complex or Plant Magic Soil (see our Hesi feed chart). Its page calls it ideal for young plants. It is the soil in our 4-Pot Soil & Nutrient Bundle, 8-Pot Soil & Nutrient Bundle and 16-Pot Soil & Nutrient Bundle, with fabric pots and Intense Dirt feeds.

Which soil should I choose?

Seedlings and cuttings: a light mix in small pots. See sowing seeds indoors.
First soil grow: the Professional Plus page advises a soil already primed with nutrients, such as Canna Terra Professional (ideal for beginners, its page says). Or take the 4-Pot bundle: its page says it suits first-time soil growers, and the feeds come with it.
Following a feed chart from early on: Biobizz Light Mix or Plagron Lightmix; Canna Terra Professional Plus if you are experienced. Our which nutrients guide compares the soil feeds.
Final pots, letting the soil feed first: Biobizz All Mix, Plagron Batmix or Gold Label Special Mix Gold; start feeding at the time in the table, sooner if the lower leaves turn pale (see our yellow leaves guide).
Plastic-pot Autopots: Plagron Lightmix or Canna Terra Professional Plus on a bed of Canna Aqua Clay Pebbles, as our Autopot guide recommends.
Pots that stay wet: five of these soils already list perlite, so try them as they come; more Perlite helps a mix that packs down, but not overwatering. Pots that dry out too fast: a little Vermiculite (see our perlite and vermiculite guide). Our pots guide covers the pot itself.
Leaving soil behind: see the coco coir guide or our hydroponics hub.

Whatever the soil, water until a little runs out of the bottom of the pot and let the top dry a little before the next feed, as our Canna Terra chart guide says. Our root rot guide adds that in pots the usual cause is too much water.

Quick answers

Biobizz Light Mix or All Mix?

Light Mix to control the feeding yourself, or for young plants; All Mix to let the soil feed the plant for the first 2-4 weeks. The All Mix page suggests both: Light Mix in small pots first, then All Mix.

What is the difference between Canna Terra Professional and Professional Plus?

Professional is nitrogen-rich black peat, peat moss and perlite, for beginners and professionals. Plus is white peat and tree bark with little nutrient apart from trace elements, for experienced growers who feed from the first week or two.

Plagron Batmix or Biobizz All Mix?

Both are pre-fertilised: All Mix with worm castings and Pre-Mix for the first 2-4 weeks, Batmix with bat guano for around 3-4 weeks on tap water. Our Biobizz feed chart has a schedule written for All Mix; the Batmix page gives none.

What is the best potting soil for a greenhouse?

Any of these potting soils will do for pots in a greenhouse. Two pages name outdoor growing as well as indoor: Canna Terra Professional, and Gold Label Special Mix Gold, which its page says suits flowers, fruits and vegetables in pots, beds and containers. Both carry food, so hold back feed until the plant needs it.

More Growers' Guides

Not sure what you need? Call the shop on 0117 971 3000 or pop in to the Bristol store and we'll help you pick.