A single wooden pallet will hold more herbs than most balconies have floor space for. Stand it on its side against a wall, line it, and the gaps between the slats become planting pockets — a vertical kitchen garden about a metre wide. Enough for thyme, parsley, chives and mint, with a pocket left over for salad leaves. The job takes an afternoon.
It also sidesteps the problem that defeats most small-space growing: floor area. Courtyards and balconies tend to be long and narrow, with plenty of wall and almost nowhere to stand a pot. Building upwards is the obvious answer, and a pallet is already built for it — slatted, strong, and designed to let air and water through.
Why a pallet works for herbs
Most culinary herbs are not greedy. Thyme, oregano, sage and rosemary evolved on thin, stony ground and grow better in cramped, free-draining conditions than in deep, rich soil. A pallet pocket holds 8cm to 12cm of compost and drains freely, which suits them.
There is a limit. Rosemary and bay want 25cm or more of root room, so give them the deepest pocket or stand a potted one on top of the planter. Soft herbs — parsley, coriander, chives, basil — are happy in the shallower pockets as long as you water them properly.
Choose the right pallet
Look for the stamp burned into the wood. HT means heat-treated, which is what you want; MB means the pallet was fumigated with methyl bromide, so leave it where it is. Avoid anything stained, spilled on or smelling of chemicals, because you cannot know what it carried.
Pallets from builders' merchants, garden centres and delivery drivers are easy to find. Ask before taking one from behind a shop.
What you will need
- One wooden pallet, ideally 120cm x 80cm
- Weed-suppressing membrane or heavy-duty landscape fabric
- Staple gun and stainless staples
- Sandpaper, medium and fine, or an orbital sander
- Claw hammer or pry bar, and a hand saw
- Exterior wood screws, a drill, and two L-brackets
- Peat-free multi-purpose compost and horticultural grit
- Small herb plants in 9cm pots
Preparing the wood
Pallet wood is rough, and skipping the sanding is the mistake everyone makes once. Go over every surface you might touch — top edges and the inside of the pockets especially — with medium grit, then fine. Splinters gather where the slats meet the corner blocks.
Leave the timber bare if you like the weathered grey, or stain the outside only, using a water-based product suitable for plants. Let it cure fully before planting.
If you only do one thing well, line the back properly. A leaky planter sours the whole idea; everything else can be improved next spring.
Building it, step by step
- Decide which face will sit against the wall — the side with the most slats still in place.
- On the front face, remove every third slat, using a hammer with a block of wood to protect the timber, or a pry bar. Keep the slats you take off.
- Sand everything.
- Line the back, base and sides with membrane, stapling it taut and folding the corners rather than bunching them. Leave the front open.
- Pierce drainage holes through the membrane at the lowest point of each pocket.
- Screw two of the removed slats across the bottom front as a lip, to stop compost washing out.
- Stand it against the wall and secure it with L-brackets or a strap around a railing. Sit the base on two bricks or timber offcuts so it is not standing in water.
Planting it up
Mix compost with roughly a quarter grit by volume. It feels like a lot, but shallow pockets drain poorly with straight multipurpose compost, and Mediterranean herbs prefer the grit.
Fill each pocket, firming gently, and plant into the gaps rather than pushing roots through the slats. Leave a centimetre of space below the top edge so water does not run straight off.
Put the thirstiest plants — mint, parsley, coriander — in the lower pockets where they are easy to reach with a watering can, and give the top pocket to thyme or oregano, which cope with drying out. Mint spreads aggressively, so sink the whole pot into the pocket rather than planting it bare.
Watering and keeping it going
Vertical planters dry out faster than a border, and shallow pockets faster still. Check daily in summer by pushing a finger into the compost, water in the morning, and water each pocket individually rather than pouring from the top. A layer of gravel on the surface slows evaporation and keeps compost off the leaves.
Feed leafy herbs every fortnight with diluted liquid tomato feed. Woody herbs such as rosemary and thyme need far less; too much food makes them floppy and bland.
Harvest by pinching out the tips, and cut flower spikes off basil to keep the leaves coming. Trim thyme, oregano and sage after flowering so they do not go woody. In autumn, move the planter into shelter, cut back the watering, and lift it off cold paving. Each spring, scrape out the top 5cm of compost and replace it.
One pallet, a season of suppers
Start with four or five herbs you actually cook with, rather than a full set that looks lovely in June and is ignored by August. Thyme, parsley, chives and mint cover most of what a kitchen needs.
When the planter has come through a winter and is still standing straight, you will know the afternoon was well spent. If a plant dies, replace it — nothing in a small garden has to be permanent.
Photo: Kindel Media / Pexels
