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How to choose potting compost for pots and baskets

Updated: October 2026

You have empty patio pots, a peace lily that has outgrown its pot, and a search page that calls the same sack potting soil, multi-purpose compost and houseplant mix. How to choose potting compost is the order to use before you open the [potting soil comparison](/hub/fertiliser-soil-and-bark-mulch/potting-soil): the job first, then the peat line, then the litres you can lift and store. Price per litre comes last. This page does not rank the nine amazon.co.uk bags. The Products Compared editorial team read the listings plus public notes from the RHS and Which?. We did not run a pot trial. A qualifying purchase through a link can earn a commission at no extra cost to you.

You have empty patio pots, a peace lily that has outgrown its pot, and a search page that calls the same sack potting soil, multi-purpose compost and houseplant mix.

Our top picks

Munnie Munnie multi-purpose compost 60 L

Best overall

Munnie Munnie multi-purpose compost 60 L
9.2/10about £9.34
View offer
GROWMOOR Growmoor multi-purpose compost 60 L

Rank 2

GROWMOOR Growmoor multi-purpose compost 60 L
9.0/10about £13.98
View offer
Miracle-Gro Miracle-Gro houseplant potting mix 10 L

Alternative

Miracle-Gro Miracle-Gro houseplant potting mix 10 L
8.6/10about £8.99
View offer
On this page
  1. 1.Potting soil or potting compost
  2. 2.Match the bag to the job
  3. 3.Litres, packs and what you can lift
  4. 4.Peat, organic wording and bag condition

Potting soil or potting compost

In the UK the product for a pot is bagged potting compost. Potting soil on an amazon.co.uk title is usually the same aisle, not garden soil and not homemade heap compost. Garden Organic draws that line: heap compost is a soil improver, and potting compost is a growing medium for a container. Growmoor names seeds, cuttings, pots, baskets, beds and borders on one 60 litre listing. Munnie covers indoor and outdoor plants. Laeto adds lawn top dressing. A houseplant mix is a smaller bag. A coir brick expands with water.

Match the bag to the job

Patio tubs want a multi-purpose sack, usually 50-120 litres: Growmoor 60 litres at about £13.98, Munnie's 60 litre title at about £9.34, the Growmoor twin at about £21.71, and Laeto 120 litres at about £24.99. A windowsill plant wants 8 to 10 litres. Miracle-Gro is about £8.99. Houseplant Focus, two peat-free 8 litre bags, is about £17.98, about 90p to £1.12 a litre against about 16p to 23p on a large sack. Indoor drainage is on houseplant potting mix. A brick is a third type. DIVCHI at about £7.70 arrives, on the first 50 reviews, as a 680 g block. PLANT!T at about £9.86 expands to a claimed 15 litres after 6 to 8 litres of water, peat-free with nothing added, so you feed it.
Munnie Munnie multi-purpose compost 60 L

Testsieger

Munnie Munnie multi-purpose compost 60 L
9.2/10about £9.34
View offer

Litres, packs and what you can lift

Read the title litres, then the pack field. Growmoor's single 60 litre bag lists 14 kg, about 23.3p a litre, so litres and weight agree. Munnie lists 14.9 kg and a pack count of 2, so about £9.34 is not a proven price per litre until you count the bags. The Growmoor twin says 2 x 60 L while the volume field says 60 litres. Laeto states 120 litres at about 20.8p a litre, and at least one review describes 40 litre bags. Houseplant Focus lists 1.2 kg against 16 litres. In a flat, the 10 litre bag is the practical buy even when the sack looks cheaper per litre.

Peat, organic wording and bag condition

Peat-free is a printed claim. The RHS says a bag that does not say peat-free most likely is not. Organic wording does not stand in. England announced a retail ban for 2024. By 2026 no statute was in force. Label rules are on peat-free potting compost. Only Houseplant Focus prints peat-free on the title and bullets. PLANT!T's listing says peat-free with nothing added. Munnie's reduction is not those words. Growmoor, both Miracle-Gro faces, DIVCHI and Laeto have no peat-free line. A Laeto review is not the label. Which? says use a fresh bag within about three months. Miracle-Gro's 10 litre mix is the face that claims a feed for up to three months.

Common questions

Is potting soil the same as potting compost?
On a UK shopping page, potting soil is usually bagged potting compost: a container growing medium, not garden soil and not homemade heap compost. Titles mix the words on the same product. Judge the bag by the job it names and by whether it prints peat-free, not by which of those two phrases sits in the title.
What size bag do I need for patio pots?
Use a 50 to 120 litre multi-purpose sack for a run of patio pots, and a 10 litre bag only if you are filling one or two small containers. Growmoor's single 60 litre listing is 14 kg. Munnie's 60 litre title is 14.9 kg with a pack field that says 2. A patio-guide figure of five or six small pots from 50 litres is a rule of thumb, not a measured fill from this set.
Can I use multi-purpose compost for houseplants?
You can, and several 60 litre titles mention indoor plants. A dedicated 8 to 10 litre houseplant mix is still the better default in a flat, because the sack is smaller and the texture is usually finer or more free-draining. A 14 kg patio sack in a hallway is a storage problem before it is a plant problem.
How do I know if a bag is peat-free?
Only the words peat-free count. The RHS says a bag that does not print them most likely is not peat-free. Organic, eco-friendly, and a reduction in peat use are different sentences. In this comparison Houseplant Focus prints peat-free. PLANT!T's listing says peat-free. Munnie's reduction line does not.
Is a compressed brick ready to use?
No. DIVCHI reviews describe a block that expands after you add water. PLANT!T tells you to add 6 to 8 litres of water to reach a claimed 15 litres, and the listing says nothing added, so you feed it. A brick is a storage format, not a loose bag you can pot from on the doorstep.
How long does the feed in a bag last?
Which? treats about four weeks as the usual starter window unless the bag claims longer. Miracle-Gro's 10 litre houseplant mix claims a feed for up to three months. That is that listing. Growmoor, Munnie and Laeto do not print a duration you can copy across.

Related pages

Best potting compost in this set

Potting soil

Houseplant potting mix UK for one or two indoor pots

How to use potting compost in pots and coir bricks

Peat-free potting compost UK: what the bag must say

Sources

Public UK sources from the research digest, used for this page in October 2026. Prices, stars and review counts are from the nine amazon.co.uk listings captured on 21 October 2026. Peat-free means the listing prints those words. Organic wording is not a certificate. This page did not measure fill volume or run a growth trial.

  1. RHS, peat-free choices (retrieved 21 October 2026)
  2. RHS, how to plant a container (retrieved 21 October 2026)
  3. RHS, minimising health risks in the garden (retrieved 21 October 2026)
  4. RHS, retail peat-free from 2026 (retrieved 21 October 2026)
  5. Which?, best compost 2026 (retrieved 21 October 2026)
  6. Which?, peat-free compost for patio pots (retrieved 21 October 2026)
  7. GOV.UK, sale of horticultural peat (retrieved 21 October 2026)
  8. Garden Organic, garden compost or potting compost (retrieved 21 October 2026)