We started supplying hemp and cannabis growers in 2022, assuming it was a straightforward bulk container application. It was not, and the first season was an education we paid for.
Season one: what we got wrong
We supplied standard 48 × 40 × 36 triple-wall gaylords with 4-mil poly liners. Three problems appeared within weeks.
- Cube. Dried biomass runs 6 to 12 lb per cubic foot. A 40-cubic-foot container was weight-limited at nothing and cube-limited immediately. Growers were paying to ship air inside a container designed for dense material.
- Odour. Standard poly is not an odour barrier. Containers in shared storage and on shared trailers created problems we had not anticipated.
- Moisture. Biomass arriving at 10–12% moisture respires. In a sealed liner that moisture redistributes and the board gets the worst of it.
What the container looks like now
| Element | Specification | Why |
|---|---|---|
| Dimensions | 48" × 40" × 60" | 66.7 ft³ — cube is the binding constraint |
| Wall | Triple wall, 1,100 lb test | Height needs the stiffness |
| Lid | Full telescoping cap | Top-edge protection and containment |
| Liner | Multi-layer odour barrier | Standard poly is not sufficient |
| Bottom | Separate tray | Lifts the cut edge off the pallet deck |
| Marking | Lot identification panel | Traceability requirement |
The odour barrier question
This is the specification that growers most often try to economise on and most often regret. A standard poly liner is a moisture barrier, not an odour barrier — the molecules responsible for aroma pass through ordinary polyethylene readily.
Multi-layer barrier liners, typically incorporating an EVOH or metallised layer, are substantially more effective. They cost more. They also stop your product perfuming a shared trailer, which has commercial consequences well beyond the packaging line.
Moisture management
Biomass is not inert. It respires, and in a fully sealed container that produces a humid microclimate that softens the board from the inside and can affect the product.
Our current recommendation is a liner that is closed but not hermetically sealed — folded and clipped rather than heat-sealed — plus storage under roof on pallets, never on concrete. Growers who follow that get 8 to 10 trips from a harvest bin. Growers who seal hard and store on a slab get 3 or 4.
The enemy of a harvest bin is not the load. It is the humidity the load generates in a sealed container on a cold floor.
Traceability
Regulatory regimes vary by jurisdiction and change often, but the common requirement is lot-level traceability through the supply chain. Practically this means a durable marking panel that survives the trip, and a destruction path for marked containers that cannot simply be resold.
We handle that as a closed pool: marked containers come back to us, are either reconditioned for the same customer or securely destroyed, and never enter general saleable stock. It is more administration than a normal container pool and it is not optional.
Season three numbers
Across the growers we supply, median trips per harvest bin has gone from 3.1 in the first season to 8.4 in the third. Almost none of that improvement came from better board. It came from the lid, the separate bottom, the barrier liner, and getting containers off concrete floors.
What we would tell a first-season grower
- Specify for cube, not weight. A 60-inch bin, not a 36-inch one.
- Budget for the barrier liner. It is not where to save money.
- Buy the lid and the bottom tray. Together they are worth several trips.
- Commit to a pool in March for an August need. Pre-season availability and pricing are not comparable to September.
- Store under roof, on pallets, always.
- Agree the destruction path for marked containers before you need it.
Our pieces are written by the people who do the work rather than by a content agency, which is why they contain more numbers and fewer adjectives than is fashionable. If a figure here does not match your experience, we would genuinely like to hear about it — two of our published coefficients have changed that way.