In short: Coco logs (also sold as coir logs) are compressed rolls of coconut-husk fibre used to line hanging baskets and planters, stabilise slopes and edge borders. They are made from the same renewable husk as coco coir growing medium, but serve a structural job rather than a growing one — for actual planting volume, a compressed coir brick gives far more usable medium per pound.
What is a coco log?
A coco log is coconut fibre — usually the long, coarse strands rather than the fine pith — rolled and bound into a dense cylinder, typically 30 cm to 2 m long. Unlike a coco coir brick, which is designed to break apart and expand into loose growing medium, a log is designed to hold its shape for a season or more.
What coco logs are used for
- Hanging basket and trough liners — the classic use: the fibre holds compost in while draining freely.
- Slope and bank stabilisation — landscapers pin logs across slopes to slow run-off while planting establishes.
- Pond and border edging — a natural-looking edge that plants can root through.
- Wildlife-friendly structure — the fibre weave shelters insects while it slowly breaks down.
Coco log vs coco coir brick — which do you need?
| Coco log | Coco coir brick | |
|---|---|---|
| Made from | Long husk fibres, rolled | Fine coir pith, compressed |
| Job | Structure: liners, edges, slopes | Growing medium: pots, beds, trays |
| Expands with water? | No — holds shape | Yes — 5 kg brick → ~75 L in 20–30 minutes |
| Plant into it? | Through it, into compost behind | Directly, with feeding |
| Typical cost | £8–£25 per log | £16.99 for 75 L (~23p/litre) |
Can you grow directly in a coco log?
Strawberry and salad "planting logs" do exist — pre-cut pockets filled with growing medium. For everything else, treat the log as the container and fill behind it with proper medium: a blend of expanded coir and compost works well because it stays light and re-wets easily in exposed baskets. Our mix ratio guide covers the blends.
Frequently asked questions
How long do coco logs last?
Outdoors, one to three seasons depending on moisture and handling. They break down gradually into a soil conditioner rather than failing suddenly.
Are coco logs peat-free and sustainable?
Yes — like all coir products they are made from coconut husk, a by-product of the coconut harvest, and contain no peat.
Do coco logs contain nutrients?
Very few — like all unenriched coir products they provide structure, not feed. Plants rooting through a log should be fed via the medium behind it.
Need growing medium rather than structure?
A single 5 kg buffered coco coir brick (£16.99) expands to ~75 litres — pH 5.5–6.5, EC ≤0.5 mS/cm, batch-tested. Work out how much you need.