Why Brick Edging Earns Its Place

A crisp line between paving and planting does more for a small garden than almost any other cheap intervention. It tells the eye where the hard landscaping stops and the growing begins, keeps gravel out of the border and soil off the patio, and gives even a modest courtyard a sense of having been properly thought through. Reclaimed bricks are ideal for the job: they are heavy enough to stay put, they weather beautifully, and if you keep an eye on local listings, skip hire yards and reclamation merchants, they often cost very little.

There is one caveat, and it is the reason so many brick edges end up looking tired within a year. A brick laid straight onto soil, or bedded on a couple of centimetres of dry sand, will move. Frost lifts it, rain softens the ground beneath, and by February your neat line has developed a kink that no amount of kicking will fix. Do the base properly and the edge will outlast most of the plants behind it.

Choosing the Right Bricks

Not all reclaimed bricks behave the same way. Old clay bricks fired hard, often called engineering bricks, are dense, frost-resistant and heavy, and they are the best choice for edging that will be walked over or sat on. Softer, more porous bricks salvaged from internal walls will absorb water and can spall after a few hard winters, particularly in exposed northern gardens.

Roughly aim for a brick depth of 65–75mm and a length of around 215mm. A quick check when you are sorting your pile:

• Tap two together. A clear ring means a hard, well-fired brick. A dull thud suggests something softer.
• Look at the arrises. Sharp, intact corners mean the brick has not been too badly knocked about.
• Avoid anything crumbly or salt-encrusted. White bloom on the surface often points to ongoing damp problems.
• Mix your colours deliberately. Reds, buffs and blues together look far better than a single flat tone.

You will also need a bag of sharp sand, a bag of cement if you are going the mortar route, a rubber mallet, a spirit level, a string line and a club hammer or bolster chisel for cutting.

Marking Out and Digging the Trench

Run a string line along the intended edge, pulling it tight between two stout pegs. For a curve, bend a length of hose or rope to the shape you want and trickle sharp sand along it as a guide, then remove the hose before you dig.

Dig a trench about 150mm wide and deep enough for your chosen base plus the brick. For a mortar bed, allow roughly 60mm for the mortar and 70mm for the brick, so around 130mm total. For a dry-laid edge on a compacted sub-base, you want a little more depth to accommodate 75–100mm of compacted hardcore.

Keep the trench bottom flat and firm. Tamp it with the end of a piece of timber, then check the depth every metre or so with a tape. A wobbly trench bottom is the single most common reason an edge ends up uneven.

Setting Bricks on a Firm Base

There are two sensible approaches, and both will hold through a hard frost.

The mortar bed method suits straight runs and gentle curves, and it is the quickest for a beginner. Mix four parts sharp sand to one part cement with just enough water to make a stiff, crumbly mortar that holds its shape when squeezed. Lay a bed roughly 50mm deep along a metre of trench, then press each brick into it with a gentle twist, checking level across and along with your spirit level. Tap down with the rubber mallet, never a metal hammer, which will chip the corners.

The dry-laid method on compacted hardcore is better where you want drainage, and it allows you to lift and reposition a brick later. Fill the trench with 75–100mm of MOT Type 1 or similar, compact it thoroughly, then screed a thin layer of sharp sand over the top. Bed the bricks onto that, tapping each one level. Brush more sand into the joints at the end and water it in.

Whichever route you take, leave a joint of 8–10mm between bricks. Butt-jointing them tight looks neat for a fortnight and then causes trouble, as there is no room for expansion or for the sand that knits the whole run together.

Corners, Curves and Cutting In

For a right-angled corner, lay one brick lengthwise and the next one across it, alternating as you go, so the joint patterns interlock. This is far stronger than simply butting two runs together.

Curves are easiest with the brick laid lengthwise, as the slight taper of the joints absorbs the bend. If the radius is tight, use half-bricks or set them at a slight angle to one another. Cut bricks with a bolster chisel and club hammer, scoring all four faces first and then striking firmly. Wear safety glasses; fragments fly.

Where the edge meets a wall or a step, cut the final brick to fit snugly. Gaps left at junctions are where water gets in and where frost does its worst.

Finishing and Looking After the Edge

Once the run is laid, check it with a straight edge and a level, adjusting any brick that sits proud. Leave mortar to cure for at least 24 hours before walking on it, and keep it damp if the weather is hot and dry. Point the joints with a pointing trowel or a jointer, then brush the surface clean before the mortar sets hard.

For the first winter, keep an eye on the edge after heavy frost. If a brick lifts, lift it out, refresh the bed beneath and reset it. That small bit of maintenance in year one is usually all it takes, and after that a brick edge in a small garden simply settles down and gets on with the job of making the whole space look considered.