A planter takes two to five days of workshop time. Here's where it goes.
Most "wooden planters" you'll find online are thin boards stapled or screwed together at the corners. They look fine in the photos and last a season or two before they warp, the corners gap, and the whole thing starts to lean. HEWN planters are different — and the difference is in the things you don't see straight away.
The timber
Every HEWN piece is built from 150×50mm pressure-treated structural softwood. That's the same dimension and grade of timber used to frame timber-frame houses, joist out floors, or build deck substructures. It's not the same stuff most garden planters are made from — those are typically 18–22mm cladding or fence boards, dressed up to look chunky.
Pick up a Gwern Planter and you'll notice immediately: a single course of the smallest size weighs more than most flat-pack planters fully assembled. That weight is the timber doing real structural work, not decoration.
The wood is sourced from a local Flintshire timber merchant — pressure-treated to Use Class 3 standard (suitable for permanent outdoor exposure, in or above ground). It carries the standard 15-year warranty against decay, but in practice, with the way HEWN planters are built (raised off the ground on bearers, with proper drainage), they tend to outlast that comfortably.
A note on safety, especially for vegetables
This question comes up a lot, so an honest answer up front: yes, modern pressure-treated wood is safe for growing vegetables.
The reason it's worth saying out loud is that there's a lot of out-of-date advice online warning against treated timber for veg beds. That advice was correct twenty years ago, when the standard treatment was CCA (chromated copper arsenate) — which contained, as the name suggests, arsenic. CCA-treated timber was banned from sale in the UK in September 2006.
Modern UK pressure-treated timber uses Tanalith E, a copper-triazole treatment. The Soil Association — the UK's main organic certification body — explicitly confirms that pre-treated timber is suitable for organic vegetable beds and compost bins. As long as the timber is fully dry before use (which all HEWN timber is, before it ever gets cut), it's good for tomatoes, herbs, salad, the lot.
If you're still unsure, you've got two simple options: line the inside of the planter with a layer of polythene before adding compost (we can include this on request), or grow ornamentals in the HEWN piece and run vegetables in a separate bed. Either is fine.
The joinery
This is the bit most planter-makers skip, and it's the bit that most matters.
Every corner of every HEWN piece is hand-cut and notched, so each course of timber locks into the next. Imagine a log cabin — the timbers cross at the corners, and the corner is held together by the geometry of the cut, not by fasteners. Same idea, scaled down to a planter.
What this means in practice: there are no exposed screws on the visible faces of the planter. There are no thin metal brackets on the inside corners. The structural integrity comes from the timber itself, the way buildings work.
Cutting the notches by hand on every corner takes time. A Gwern Planter has 12 corner joints; a Trellis Planter has 16+. Each one is marked, cut, and dry-fitted before the piece is assembled. It's the slowest part of the build, and it's why a HEWN planter takes days where a flat-pack equivalent takes minutes.
The structural integrity comes from the timber itself, the way buildings work.
Base, drainage, and the bits underneath
A planter that sits flat on the ground will rot from the bottom up, no matter how good the corners are. Every HEWN piece is built on raised bearers — short timber feet that lift the base 25–30mm off whatever surface it's standing on, allowing air to circulate and water to drain away.
The base itself has drainage gaps built in (not just drilled holes — full-width gaps between the floor slats), so excess water never sits. For the Trellis Planter, the same principle applies, with the added benefit that the castor wheels also keep the base off the ground.
I include a roll of permeable membrane liner with every piece — fit it before adding compost and it stops fine soil from washing through the drainage gaps onto your patio.
The maker's mark
The last step before a piece leaves the workshop is the HEWN mark, burned into the corner with a branding iron. It's small. You have to look for it. But it's there as a small promise: if anything ever goes wrong with the piece — a corner shifts, a board splits, a screw works loose — you know exactly where it came from, and I want to hear about it.
Lead times, honestly
I'm one person, working from a workshop in the woods, and I build to order. So lead times depend partly on how busy I am when your order lands.
- Gwern Planter (Small or Medium): 2–3 days of build time, usually delivered within 7 days
- Gwern Planter (Large) or custom dimensions: 3–4 days of build, 7–10 days to delivery
- Trellis Planter (either size): 4–5 days of build, 7–14 days to delivery
If you've got a specific deadline — a birthday, a finished patio, a garden party — say so when you enquire. I can almost always work around it, and I'd rather tell you straight that something isn't possible than promise it and miss.