Planting a fragrant herb path beside the back door

Why the back door is the best site on the plot

The strip of ground beside a back door takes a beating. It is where boots land, where the dog waits, where the tap drips, and where nothing much gets planted because it reads as a thoroughfare rather than a border. That is precisely what makes it the ideal place for a herb path. Every time you step out to the bin, the log store or the washing line, you brush past leaves and release scent — a small daily pleasure that costs very little and asks almost nothing once it is established.

It also solves a practical problem. A gravel strip over free-draining herbs keeps mud off the kitchen floor, needs no mowing, and shrugs off drought far better than a lawn. If your back door faces south or west and catches five or six hours of sun, you have the conditions these plants want. A little shelter from the worst of the wind helps, too, which is why a wall, a fence or the side of the house makes such a good backdrop.

The three herbs worth building a path around

There is no need to be adventurous. Three plants do the job beautifully, and all three release their scent on contact rather than needing to be picked.

• Thyme — the backbone of any herb path. Common thyme (Thymus vulgaris) is compact and intensely aromatic, but for sheer ground-covering speed look at creeping varieties such as Thymus serpyllum or the silver-edged Thymus ‘Silver Posie’. Thyme wants full sun and grit, and it will happily knit itself into the gravel.
• Lavender — choose English lavender rather than the tender French or Spanish sorts, which sulk in a wet British winter. Lavandula angustifolia ‘Hidcote’ and ‘Munstead’ are both compact, hardy and generous with scent. Plant them at the edges and corners of the path where you will brush against them, and keep them well away from the drip line of the roof, which can drown them.
• Chamomile — for the soft, apple-scented note. The non-flowering form, often sold as Chamaemelum nobile ‘Treneague’, makes a low, springy mat and never sets seed, so it stays tidy between the stones. It is the least drought-proof of the three and appreciates a little shade in the hottest part of the day.

If you have room, add a clump of oregano or winter savory for the bees, but keep them to the edges — both can sprawl and smother their neighbours.

Building the path: drainage before decoration

The single reason herb paths fail is that the plants sit in wet, airless soil through winter. Fix that first and the rest is easy.

Mark out a strip about 60cm to 90cm wide and lift the top 10cm of turf and soil. On heavy clay, break up the subsoil with a fork to a spade’s depth and add a barrow of sharp sand or horticultural grit per square metre. Then lay a sub-base of about 50mm of compacted MOT Type 1 or similar crushed stone, whacked down firmly. Top it with 30mm to 40mm of gravel — 10mm pea gravel is comfortable underfoot and lets seedlings settle, while 6mm grit suits chamomile better. Keep the finished level just below any door threshold and a good 20mm below a damp course.

Skip the weed membrane, or if you use it, cut generous crosses rather than slots. Fabric stops the plants rooting into the sub-base, encourages them to sit wet, and prevents the gentle self-seeding that makes a path like this feel established. A thick gravel mulch does most of the weed-suppressing work on its own, and what does come through is easy to tease out with a hand fork.

Planting through the gravel

Plant in spring or early autumn, when the soil is warm and damp but not cold. Water the pots thoroughly the night before, then pull the gravel aside to make a planting pocket wide enough for the rootball. Set the plant so the crown sits fractionally proud of the surrounding gravel — not buried — and firm it in with your knuckles.

Space thymes 25cm to 30cm apart, dwarf lavenders 45cm, and larger lavender 60cm to 90cm. Push the gravel back around the collar but keep it clear of the stems themselves, as a damp mulch against the neck of a lavender is an invitation to rot. Water in well and keep watering once a week for the first summer only; after that, these plants should be left to fend for themselves.

The first year and the years after

Feed nothing. Rich soil makes thyme and lavender floppy and short-lived; lean conditions are exactly what you want. The main jobs are trimming and weeding.

• Clip lavender straight after flowering, in mid to late August, taking off the flower stems plus a couple of centimetres of leaf. Never cut into the old, leafless wood — it rarely regrows.
• Shear thyme lightly after its midsummer flush to keep it dense and prevent it going woody in the middle.
• Top up the gravel by a centimetre or two each spring.
• In a wet winter, lift a pot or a slate over the worst-exposed lavender if the ground is waterlogged.

Replace straggly plants every four or five years. Thyme and lavender are cheap to raise from cuttings, and a path is only ever as good as its youngest plants.

Tight spots, shady doors and pots

Not every back door opens onto a sun-baked yard. North-facing thresholds, narrow passages and rented gardens all have workarounds. Where there is only a metre of concrete, stand three or four terracotta pots of thyme and lavender along the edge — the same brushing release of scent, no digging required, and you can move them to chase the sun. Use a gritty, soil-based compost and raise pots onto feet so they drain freely.

For shaded doorways, swap the lavender for sweet cicely, mint or lemon balm, which tolerate less sun and still scent the air when disturbed. Keep mint in a pot sunk into the gravel unless you want a mint path, which, given a season, is exactly what you will get.