Upcycling Wood Pallets into Garden Planters

Identifying which pallets are safe to use

Not all wood pallets are appropriate for contact with soil and growing edibles. The stamp on the pallet indicates how the wood was treated during manufacture or international transport. This matters most when building planters for food crops like herbs or vegetables.

Pallet markings explained

HT — Heat Treated. The wood was heated to a core temperature sufficient to kill pests. No chemical treatment. Safe for edible crops.
DB — Debarked. No pest treatment, just debarking. Generally safe, though the absence of heat treatment means it may still harbour insects.
KD — Kiln Dried. Heat dried in a kiln. No chemical treatment. Safe.
MB — Methyl Bromide treated. A fumigant used for pest control in cross-border shipments. Avoid for planters, particularly food gardens.
No stamp visible — Unknown treatment history. Avoid if using for edibles; acceptable for purely decorative planters.

Where to find HT pallets in Canada

Grocery distribution centres, bakeries, tile and flooring suppliers, and garden centres often have surplus HT pallets. Local Facebook Marketplace and Kijiji listings in most Canadian cities regularly post free pallets. Some municipalities also offer reclaimed wood at community resource depots — Toronto, Vancouver, and Calgary all have active programs as of recent years.

What this guide builds

The primary project here is a leaning vertical pallet planter: a single pallet stood on end, angled slightly against a fence or wall, with landscaping fabric stapled to the back and sides to form soil pockets between the slats. This format works for herbs, strawberries, shallow-rooted lettuce varieties, and ornamental plants like nasturtium.

A secondary project in this guide adapts a pallet lying flat as a raised bed liner — useful for small decks where soil volume matters more than visual density.

Tools and materials

Tools required

Circular saw or handsaw (for trimming pallet overhang if needed)
Staple gun with 10–12 mm staples
Hammer and pry bar (for removing damaged slats)
Wire brush (for cleaning the wood surface)
Paintbrush, 50 mm wide

Materials

One HT-stamped wooden pallet, 1200 × 1000 mm (standard GMA pallet) or similar
Landscaping fabric, 1–1.5 m² (available at RONA, Home Depot Canada, or Canadian Tire)
Exterior wood stain or linseed oil — one litre covers two to three pallets
Potting mix appropriate for the intended crops (not garden soil, which compacts)
Two L-brackets and 50 mm screws if attaching to a fence
Optional: 5 cm casters for moveable planter versions

Step-by-step: vertical leaning planter

Inspect and clean the pallet

Check all boards for splits, protruding nails, and soft spots that indicate rot. A pallet that has been left outdoors for more than one Canadian winter may have waterlogged sections — press firmly on each board to test. Soft sections should be pried off with the flat bar and replaced with matching lumber from offcuts if available, or simply left open.

Use the wire brush to remove dirt, debris, and loose wood fibres from all surfaces. If the pallet smells of chemicals despite an HT stamp, set it aside — some pallets are restamped by distributors and may not reflect original treatment. The smell of petroleum, solvent, or sharp industrial odour is a useful indicator.

Apply exterior stain or oil

Untreated pallet wood weathers quickly in Canadian conditions — moisture cycling through freeze-thaw from November to March accelerates cracking significantly. A single coat of exterior wood stain or raw linseed oil extends the useful life by two to three years. Apply with a wide brush, working the oil or stain into the end grain of each board, which absorbs most. Allow 24 hours of drying time before proceeding.

Use linseed oil for edible crops rather than stained finishes. Raw linseed oil (not boiled, which contains metallic driers) is considered food-safe once fully cured, typically after one week in above-15°C temperatures.

Attach the landscaping fabric

Lay the pallet flat, back-side up. Cut the landscaping fabric to cover the entire back face plus a 10 cm wrap around each side. Starting at one side, staple the fabric to the top edge of the pallet every 10–12 cm. Pull the fabric taut down to the bottom and staple the lower edge. Wrap and staple both sides. The fabric should be under slight tension — loose fabric sags when filled with soil.

The purpose of the fabric is to hold soil in the planting pockets while allowing drainage. Heavy-weight landscaping fabric (80–100 g/m²) holds shape better than light-duty versions over multiple seasons.

Position and secure the pallet

Stand the pallet upright against the fence or wall at a 10–15 degree lean. A perfectly vertical pallet filled with soil is unstable — the lean moves the centre of mass back toward the support. For a fence-mounted version, drive two L-brackets into the top horizontal rail of the pallet and attach them to the fence boards with 50 mm screws. This allows the pallet to stand independent of the lean once the brackets are in place.

On a deck, place rubber furniture pads under the two contact points to prevent surface staining from the wood stain or soil moisture.

Fill with soil and plant

With the pallet still lying flat and the fabric face up, pack potting mix into each pocket formed between the pallet slats and the fabric. Use a trowel to press the mix firmly — air pockets reduce root contact. Fill each pocket to within 2 cm of the top slat edge.

Plant directly into the exposed soil surface in each pocket. Shallow-rooted plants — herbs like basil, thyme, and chives, or lettuce varieties like 'Little Gem' and 'Black Seeded Simpson' — establish well in the 15–20 cm depth that pallet pocket soil provides. Plant and allow the pallet to lie flat for one week before standing it upright. This gives roots time to anchor before gravity pulls the soil downward.

Adapting a pallet as a flat raised bed liner

For a deck-based raised bed, a pallet laid horizontally inside a simple frame of four 2 × 6 lumber boards provides a base that elevates soil away from the deck surface and encourages drainage. The gaps between pallet slats allow excess water to flow through. Line the interior with landscape fabric before adding soil to prevent fine particles from washing through the gaps.

A standard GMA pallet (1200 × 1000 mm) inside a box of matching interior dimensions creates a raised bed approximately 20 cm deep — adequate for most herbs and annual vegetables grown in Canadian growing zones 5–8 (most of southern Ontario, BC's Lower Mainland, and southern Alberta).

Seasonal maintenance in a Canadian climate

At the end of the growing season, remove the soil from vertical pallet planters before freeze-up. Soil left in contact with pallet wood during freeze-thaw cycles forces moisture into the wood grain, significantly accelerating decay. Store the empty pallet horizontally in a garage or shed if possible.

Reapply a coat of linseed oil or wood stain each spring before replanting. Check the staples holding the landscaping fabric — harsh winter conditions can loosen them. Replace any that have pulled free before re-filling with soil.

Growing zone reference

Agriculture and Agri-Food Canada maintains a public plant hardiness zone map for Canada. Most of the country's populated areas fall in zones 5–8. Warm-season vegetables require supplemental heat in zones below 6, and frost-free dates in zone 5 (e.g., much of central Ontario) run roughly mid-May to late September.