Price does not predict compost quality. Which? Magazine has been proving this for over 30 years of independent testing. These five bags - all under £15 - outperform far more expensive options for containers, raised beds, and houseplants. One costs 22p per litre.
Why Expensive Compost Isn't Always Better
Which? Magazine has tested UK compost for over 30 years. Their consistent finding: high price does not predict high performance.
A £5 bag regularly outgrows a £20 bag on the same plants in the same conditions. The honest measure is what's in it and what grows in it.
1. Pelle & Sol 60L Multi-Purpose Compost - £12.95
Best for: Volume gardeners, raised beds, containers. Our pick.
Nutrient-enriched formula with vermiculite. 4.5 stars from 2,000+ Amazon reviews. Named best compost for bag-size variety in The Turf Doctor's February 2026 roundup. The 60L fills a standard raised bed in a single purchase at ~22p per litre.
- Formula: Nutrient-enriched soil, vermiculite
- Moisture retention: Strong
- Sizes: 10L, 20L, 40L, 50L, 60L
- Not for: Seed germination, acid-loving plants
2. Westland Multi-Purpose + John Innes - ~£9–11 for 50L
Best for: Long-term containers, perennials, shrubs.
The John Innes formula adds loam stability - right for plants living in the same container for two or more years. Rated best overall quality compost in The Turf Doctor's 2026 roundup. Widely available in garden centres and online.
- Formula: John Innes mix, loam, added nutrients
- Moisture retention: Good
- Not for: Quick seasonal bedding - overkill for one-season planting
3. Levington Multi-Purpose - ~£12–14 for 70L
Best for: Maximum volume on a tight budget.
At 70L for under £14, this is the lowest cost per litre on the list. Not peat-free. The bag converts to a grow bag when used on its side. Quality can vary - some bags contain more wood debris than others.
- Formula: Recycled materials, some peat
- Moisture retention: Good once established
- Not for: Peat-free buyers, seed sowing, indoor plants
4. Miracle-Gro All Purpose 40L - ~£12–15
Best for: Consistent results across a wide range of plants.
Waterlock technology retains moisture strongly. 19,000+ Amazon reviews at 4.5 stars. Main limitation: the most expensive per litre in this list, and 40L won't fill a raised bed.
- Formula: Peat-free, 14 minerals, smart-release granules
- Moisture retention: Very strong
- Not for: Volume gardening - highest price per litre here
5. GreenBrokers Organic Expanding Compost - ~£8–12
Best for: Flat-dwellers, balconies, minimal storage.
Comes in a compressed cube - just 18×18cm - and expands to 10L when you add water. Peat-free and organic. Ideal for balconies or anyone without shed storage. More expensive per litre than a standard bag - not suited to raised beds.
- Formula: Organic, peat-free coconut coir
- Moisture retention: Good
- Not for: Raised beds, large containers, volume gardening
Our Pick
For UK gardeners who want quality, volume, and value - Pelle & Sol's 60L is the standout on this list.
At just 22p per litre, with vermiculite-based moisture retention and 2,000+ positive reviews, it outperforms most of what sits next to it on the shelf.
View Pelle & Sol Multi-Purpose Compost on Amazon