DIY Vertical Herb Wall from Recycled Pallets: A Beginner Tutorial

A blank wall beside a back door is wasted growing space. A single wooden pallet, stood on its side and lined, turns that wall into a stack of shallow planting pockets — room for eight or ten herbs without giving up a centimetre of patio. It is a forgiving first project too. The wood is already cut, the slats are already spaced, and nothing has to look perfect.

What decides whether your wall thrives or turns into a brown mess comes down to three things: choosing a safe pallet, getting the liner right, and mounting it so it does not come down in a storm. Work through those carefully and the rest is just planting.

Why a pallet suits herbs so well

Herbs mostly want two things: sun and drainage. A pallet gives you both almost for free. The gaps between slats hold a small volume of soil that dries out quickly, which is exactly what thyme, oregano and rosemary prefer, and the open structure means air moves through the whole wall instead of sitting against damp wood.

The trade-off is soil depth. Most pallet pockets give you 8–12 cm (3–5 in) of growing room, which is plenty for herbs and hopeless for tomatoes or root vegetables. Go in knowing that and the wall will meet your expectations rather than disappoint them.

Choosing a pallet you can safely grow food in

Pallets travel, and some are treated with chemicals you do not want next to your parsley. Look for the IPPC stamp burned into the wood. HT means heat treated, which is what you want. MB means fumigated with methyl bromide — leave those alone. No stamp at all is a guessing game.

• Reject anything with oily stains, chemical smells, or dark patches that could be a spill.
• Avoid painted or varnished pallets; sanding old paint is unpleasant and often unnecessary.
• Hardwood pallets last longer but weigh far more — a real consideration for a wall mount.
• Ask at a garden centre, building supplier or a shop that ships dry goods. They usually give pallets away for free.

What you will need

• One heat-treated pallet, ideally around 120 × 100 cm (48 × 40 in)
• Pry bar, hammer, and a hand saw or reciprocating saw
• Orbital sander with 80- and 120-grit pads
• Exterior screws and a drill
• Landscape fabric or geotextile — enough for a double layer
• Staple gun with stainless staples
• Two heavy-duty brackets or the timber for a French cleat
• Lightweight potting mix, plus compost for body
• A drip line or soaker hose, if your budget stretches to it

Prepping the pallet

1. Lay the pallet flat and pull any protruding or bent nails. Wear gloves; old pallet wood splits.
2. Pick the face that will point outwards and mark the top edge with a pencil so you keep your bearings.
3. Pry off every second slat from the front face. Wider openings mean bigger pockets and easier planting.
4. Sand every cut end and slat edge, going from 80 to 120 grit. You will be reaching into these pockets constantly, so this matters more than it sounds.
5. Close up the back face with exterior boards or plywood, screwed on with small gaps between them. The liner holds the soil; the boards just stop it bulging out.
6. Screw a diagonal brace across the back if the frame flexes when you lift a corner.

Lining and filling

Line the inside of the back and the bottom with landscape fabric, doubled, and staple it tight with stainless staples. Bring the fabric up the sides too. Any gap becomes a slow leak of potting mix down your wall every time it rains.

Fill the pockets with a light mix — potting compost cut with perlite or coarse grit. Garden soil is too heavy and compacts into brick within a season. Tamp it gently as you go and stop about 2 cm below the top edge of each slat, so water soaks in rather than running straight off the front.

One trick that pays off all summer: drop a length of perforated pipe or a plastic bottle with holes punched in it down through the middle of the pallet before you finish filling. Water poured into that tube reaches the lower pockets instead of stopping at the top row.

Leave the filled pallet to settle for a day or two, then top up the pockets. Soil sinks more than you expect, and a half-empty pocket dries out fast.

Mounting it safely

A filled pallet this size can weigh well over 45 kg (100 lb) once it is wet, so this is the step to slow down on. Screw a French cleat to the wall — one board with a 45-degree bevel, and a matching one on the back of the pallet. It spreads the load along its length and lets you lift the whole thing off for repotting.

Fix the wall half of the cleat into studs or masonry, never into drywall or siding alone. Keep the bottom of the pallet at least 30 cm (12 in) off the ground for airflow and to reduce splash onto the leaves. Lift it into place with two people, dry, before you fill it, so you know the fit is right.

Not sure what is behind your wall? Ask a carpenter or check with your landlord before drilling. A loaded pallet falling off a wall is an expensive lesson.

Choosing and placing your herbs

Put the thirsty, delicate plants low and the tough ones high. Water drains downwards, so the top row dries first — that is where rosemary, thyme and oregano belong. Basil, parsley, chives and coriander do better in the middle and lower pockets where a little moisture lingers.

Mint needs its own pocket or it will run through the whole wall. Most herbs want six hours of sun or more, so a south-facing wall works well in the northern hemisphere, north-facing in the southern. Plant three to five per row, resist overcrowding, and keep tall growers at the bottom so they do not shade everything above them.

Watering and keeping it going

Vertical planters dry out faster than any pot on the ground. Check by pushing a finger into a pocket every morning for the first fortnight; you will quickly learn the rhythm. Water slowly until it drips from the bottom row, ideally early in the day, and never soak the leaves in the evening.

A drip line on a timer takes the guesswork out. Otherwise, hand water with a narrow spout and aim at the soil, not the foliage. Feed lightly every three or four weeks during the growing season — herbs grown hard in lean soil taste stronger than overfed ones.

Cut often. Regular snipping keeps plants bushy instead of leggy, and it is the whole point of growing them. Come autumn, perennials in a small soil volume may not survive a hard frost; move the pallet into shelter if you can, or treat it as a fresh start each spring. Replace the top few centimetres of mix at the same time, and the wall will keep producing for years.

Photo: jhenning / Pixabay