Why Pallet Wood Is Perfect for a Garden Planter

Pallet wood has become the go-to material for makers who want a project that costs very little but looks like it came from a reclamation yard. The timber is usually pine or a similar softwood, cut into slats roughly 18–22mm thick and 100–145mm wide, and once it has weathered to that silvery grey it sits beautifully among lavender and old brick. Better still, a standard pallet gives you around 1.2 metres of usable length, so two pallets will supply more than enough stock for a decent-sized planter.

Before you start pulling anything apart, check what you have. Look for the ISPM 15 stamp burned into the wood: HT means heat treated and is perfectly safe for garden use, while MB indicates methyl bromide fumigation and should be avoided. Steer clear of painted or stained pallets too, and give a wide berth to any that smell of chemicals or have stains that suggest they once carried liquids. A quick sniff and a glance at the markings will tell you all you need to know.

Tools and Materials

This is a project you can complete in an afternoon with a fairly modest kit. Gather the following:

• One or two untreated pallets, plus a length of 45 x 45mm timber for corner posts
• A pry bar or crowbar, hammer and pincers for dismantling
• A reciprocating saw or jigsaw, and a cordless drill
• Random orbital sander with 80 and 120 grit discs
• 50mm exterior-grade or galvanised wood screws
• Water-based wood preserver that is safe for plants
• Heavy-duty pond liner or butyl liner, plus a staple gun
• Gravel, compost and a bag of horticultural grit

Buying galvanised screws matters more than you might think. Standard steel ones will rust through within a couple of seasons and the planter will start to loosen at the corners.

Breaking Down the Pallet and Preparing the Slats

Slide your pry bar between a deck board and the stringer beneath, then work along the board with firm, steady pressure rather than brute force. Pallet nails are usually twisted, so levering evenly is far kinder on the timber than yanking. Set the boards aside and knock out the remaining nails with a hammer and pincers — leaving a few bent stubs in the wood is asking for a torn hand later.

Once you have a decent pile of slats, cut them to your finished size. A planter measuring roughly 60cm long, 40cm wide and 40cm deep is a versatile size: deep enough for herbs and annuals, but still movable with two people. Sand each slat with 80 grit to kill the splinters, then go over it lightly with 120 grit. Don't sand away all the character — the saw marks and grey patina are the whole point. Apply two coats of plant-safe preserver to every face, including the ends, and let it dry fully before assembly.

Assembling the Planter

Cut four corner posts from your 45 x 45mm timber, each one 40cm long. Now build two side panels: lay five or six slats face down on a flat surface, spaced with a 3mm gap between each, and screw them to a horizontal batten running across the back. Those small gaps let air circulate and give the planter its relaxed, slatted look.

Repeat for the two shorter ends, then stand the panels up and screw them to the corner posts, working from the outside in. Check for square by measuring diagonally across the top — both measurements should match. If the planter will sit on soil rather than a patio, add a slatted base of three or four boards with gaps between them, which lets water drain freely and keeps the compost from sitting in a puddle.

Lining, Drainage and Filling

Softwood in constant contact with damp compost will rot, so a liner is not optional. Stretch your pond liner across the inside, press it into the corners and staple it over the top edge of the planter, trimming away the excess. Before you fill, pierce half a dozen drainage holes through the liner in the base, then add a 25mm layer of gravel. This keeps the compost out of the water and stops the roots sitting wet.

A simpler alternative, and one many makers prefer, is to drop a sturdy plastic trug or pot straight inside the wooden shell. The timber becomes a decorative sleeve and you can lift the pot out for repotting, which makes the whole thing far easier to maintain over the years.

Planting Up and Looking After It

Fill with a loam-based compost, such as a John Innes No. 2, mixed with a couple of handfuls of grit for drainage. For herbs, plant rosemary, thyme, sage, oregano and chives together — they all enjoy the same free-draining conditions. Keep mint in its own pot, as it will otherwise swallow the entire planter within a season. If you would rather have colour, nasturtiums, pelargoniums and cosmos all thrive in a container this size and will flower well into September.

Water little and often through the summer, and feed flowering plants fortnightly with a tomato feed. Each spring, scrape off the top 5cm of compost and replace it with fresh, and give the outside of the timber another coat of preserver. Looked after that way, a planter built from a couple of free pallets will give you years of service — and it will only look better as it ages.