Hey there, fellow DIYer,
A strip of forty centimetres against your front wall. That is all you need to turn a street made of stone into a street where something grows. And it is one of the few jobs you can finish in half a Saturday.
Straight to the answer: you make a pavement garden by lifting one or two rows of paving slabs along your front wall, digging out the yellow bedding sand to a depth of about 30 cm, replacing it with topsoil, and planting perennials that cope with drought. In most places you can do this without planning permission, as long as you stick to a strip of 30 to 60 cm wide and leave enough clear footway. Reckon on 60 to 150 euros for a strip of a few metres, and a day of work.
But there is one thing almost no pavement garden guide mentions, and it is exactly the thing you end up regretting: you must not build the soil up higher than the open perpends and airbricks at the bottom of your wall. If you do, a heavy downpour will send water straight into your cavity. That is not theory, it is one of the standard causes of damp patches low down in a wall. Further on I explain exactly what to look for.
In this article: the rules (and how to find your own council’s version in two minutes), the full step by step, which plants genuinely survive a dry, draughty spot like that, how to handle climbers without wrecking your pointing, what it costs, and the seven mistakes I see most often.
What is a pavement garden, exactly?
A pavement garden is a narrow planting strip between your front wall and the footway, made on land that is not yours. That last bit matters: the pavement almost always belongs to the council as highway authority (or sometimes to a housing association). So you get permission to make something nice of it, but the council stays the owner and can in principle remove it if the street is rebuilt or if your little garden is left to go wild.
That sounds shakier than it is in practice. Councils are generally delighted with pavement gardens: they soak up rainwater, cool the street, feed insects and make a street measurably nicer to live in. Many councils even help out by collecting the slabs for free or supplying topsoil.
Not the same as a tree pit: a tree pit is the unpaved square around a street tree. Different, sometimes stricter, rules often apply there, because you are dealing with the roots of a council tree. Do not mix the two up.
Am I allowed? The rules, and how to find your council’s
There is no single national rule for pavement gardens. Every council sets its own policy, and they genuinely differ. Most councils have a page on greening, street planting or pavement gardening on their website; if not, search your council’s site for “pavement garden” or ring the highways team.
The broad picture is the same everywhere. These are the points that come back almost every time:
| Topic | What councils usually require |
|---|---|
| Width from the wall | 30 to 60 cm, which is one to two 30 cm paving slabs. Some places work to 45 cm (a slab and a half) |
| Clear width left on the footway | UK guidance (Department for Transport, Inclusive Mobility) points to a minimum of 1.5 m clear, with 2 m preferred. Dutch councils, where these gardens have been standard for years, generally require 1.2 m, enough for a wheelchair and a pushchair to pass each other |
| Digging depth | Often a minimum of 30 cm and a maximum of 45 cm. Some councils cap it at 25 cm because of buried services |
| Permission | Usually no planning permission, but often a notification or short application first. Tenants need their landlord’s consent |
| Distance to street furniture | Keep clear around lamp posts, manhole covers and traffic signs (Utrecht, for example, requires 0.9 m around lighting columns) |
| What is not allowed | Putting up fences or railings, hiding street name plates, planting big thorny shrubs or trees |
| Maintenance | You are responsible for watering, pruning and weeding. Overhanging growth has to be cut back in good time |
| Liability | Dig deeper than allowed and hit a cable, and the damage is on you |
Two concrete examples, so you can see how much it varies. Utrecht allows a pavement garden up to 60 cm out from the wall, with at least 1.2 m of clear footway, a digging depth between 30 and 45 cm, and no permit needed as long as you own the property or have the owner’s consent. For a listed building or in a protected townscape you do have to talk to them first. Other councils, such as ‘s-Hertogenbosch, work to 45 cm wide and specify that you must not dig deeper than 25 cm because of buried services.
So here is what you do, in this order:
- Search your council’s site for pavement or front-of-house planting. Note the maximum width and the maximum digging depth
- Submit the notification or application if there is one (often a three-line form)
- Renting? Ask your landlord or housing association for written permission
- Live in a flat or a leasehold block? The front wall is usually common parts, so check with the freeholder or managing agent
- Is your house listed or in a conservation area? Ring the council, then you know for certain
Cables, pipes and checking before you dig
There is all sorts under a pavement: gas, water, electricity, telecoms, sometimes an old drain. Most utility mains sit deeper than 45 cm, but telecoms and fibre cables are sometimes surprisingly shallow. And right under your front wall your own gas supply often runs into the house.
The rules in short:
- Digging by hand with a spade, down to the depth your council allows, does not need to be reported. You feel it when you touch something and you can stop in time
- Going in with machinery (auger, mini digger)? Then check for buried services first. In the UK that means a free asset search through LSBUD or a direct enquiry to the utility companies. For a pavement garden forty centimetres wide you do not need a machine, which saves you the bother
- Feel resistance, or see yellow, red or orange sand, or a warning tape? Stop. That tape is there precisely to stop you digging further
- Hit something anyway? Do not repair it yourself. If you smell gas, get outside and call the National Gas Emergency Service on 0800 111 999
Rule of thumb: always do the last ten centimetres by hand with an ordinary garden trowel, not with a spade you put your weight on.
The pitfall almost nobody mentions: damp against your wall
Here comes the point I really want to hammer home, because this is about your house, not your plants.
Have a proper look at the bottom courses of brick on your front wall, just above the pavement. There is a good chance you will see open perpends there: vertical joints between the bricks with no mortar in them, usually a few every metre. Sometimes there are small plastic weep vents in them. They are there for a reason. They ventilate your cavity and let any rainwater that gets into it drain away again.
Build your soil up against the wall to above those perpends and this is what happens: in a heavy downpour there is standing water in your pavement garden for a while, that water runs into the cavity, and from there it can travel metres and produce damp patches on the inside. Ground level sitting too high against a wall is a classic cause of damp low down in a facade.
So:
- Keep the soil at least 5 cm below the bottom of the open perpends and airbricks. More is better
- Are your underfloor vents set low? Keep them completely clear and never cover them with soil, bark or mulch
- Give the surface of your pavement garden a slight fall away from the wall, so rainwater runs towards the footway and not towards the brickwork
- Already seeing damp patches or flaking paint low down on the inside of that wall? Sort that out before you start greening anything
One more: a pavement garden does not make your wall damp through the plants, it does it through the wrong soil level and through spraying the brickwork every day. Water the soil, not the wall.
The step by step: from slabs to greenery
Reckon on half a day to a full day for a strip of four to six metres. Dutch consumer organisation Milieu Centraal works to roughly eight hours for a standard pavement garden of 50 by 200 cm. That sounds like a lot, but digging out the sand and getting rid of it is the bulk of the job.
What you need
Tools:
– Big flat-bladed screwdriver or a small crowbar (to lift the first slab)
– Spade and an ordinary garden trowel
– Bucket or wheelbarrow
– Rake and a straight piece of timber or a spirit level
– Work gloves and knee pads
– Possibly a hand tamper to bed the remaining slab edge back down
Materials:
– Topsoil or a topsoil and compost mix, roughly 0.15 m³ per linear metre at 50 cm wide and 30 cm deep
– Plants (see the plant list further on)
– Mulch: wood chip, bark or coarse compost, a layer of 3 to 5 cm
– Optionally a concrete edging or kerb on the footway side, if your council allows it
Step 1: set your width and mark it out
Measure out from your wall the width your council allows and lay a string line or a plank there. Then walk the remaining footway with a tape measure: do you keep that clear width all the way along? On a narrow pavement you sometimes have to go back to a single row of slabs at 30 cm. That is still perfectly fine; a 30 cm pavement garden is just as full after two seasons.
Also work out where you do not want to dig: right in front of the door (you do not want to step through it), under a downpipe that is not connected to a drain, and in front of cellar hatches, wall-mounted letterboxes or meter cupboard doors.
Step 2: slabs out
The first slab is the hardest. Get a big flat-bladed screwdriver or a small crowbar into the joint and lever it up until you can get your fingers underneath. After that the rest almost comes out on its own.
Stack the slabs neatly in piles of ten on the pavement, not scattered loose. That saves carrying and keeps the route clear.
Tip: hold two or three slabs back. You can lay them flat later as stepping stones so you can reach the window when you want to clean it.
Step 3: the yellow sand out
Under the slabs there is a bed of sharp bedding sand, often 5 to 15 cm thick. That sand holds neither water nor nutrients, so most of it has to go. Milieu Centraal advises: if the sand layer is thicker than 10 cm, dig it out until no more than 10 cm remains, and mix that remaining layer with the subsoil and fresh topsoil into a loose soil layer of at least 30 cm.
In practice:
- Dig to the depth your council allows, and no deeper
- Break up the ground below with a spade without taking it out. Loosened soil lets water through, and that is exactly what you want
- Come across rubble, old setts or a slab of concrete? Take out whatever comes out without a fight and leave the rest. Half a brick never hurt anyone
- You can often get rid of the excavated sand at the council depot or tip. Give them a ring, plenty of councils collect sand and slabs from a pavement garden for free
Step 4: build an edge and check the wall side
On the footway side you want your slabs not to sink and your soil not to wash out across the pavement. Two options:
- Concrete edging or a kerb unit, set slightly above soil level. Check whether your council allows it, because some see it as an obstruction
- A row of slabs stood on edge, or one paving slab set on its side. Cheap and usually permitted
What most councils will not allow: a fence or railings. That is explicitly forbidden almost everywhere, because people can trip over it.
Now check the wall side too: where are the open perpends? Form a small channel there, so the soil clearly stays below them.
Step 5: topsoil in
Fill with topsoil to about 3 cm below pavement level. You need those 3 cm, otherwise every downpour washes your soil onto the footway.
How much soil do you need? Work out length x width x depth in metres. A pavement garden 6 metres long, 0.45 metres wide and 0.25 metres deep needs 6 x 0.45 x 0.25 = 0.68 m³, so around 680 litres. Bags of topsoil are usually 40 litres, so that is just under twenty bags. For larger quantities a bulk bag of 1 m³ works out cheaper, assuming you have somewhere on the pavement to put it.
Do not use pure potting compost. It slumps and dries out. A mix of topsoil with some compost works better: it holds water and settles less.
Step 6: putting the plants in
Stand the plants out in their pots where you think you want them, then walk back a few metres. You will almost always move two of them.
- Spacing: stick to the spacing on the label. In a narrow strip you are tempted to cram everything together, and then you are out there pruning in June
- Tall plants towards the wall, low ones towards the footway. That way nothing hangs over the pavement
- Planting hole twice as wide as the pot. Dunk the rootball in a bucket of water until no more bubbles come up, and only then plant it
- Firm it in and water straight away, even if it is raining
How many plants? Reckon roughly on 4 to 6 perennials per linear metre for a 45 cm strip, or 2 to 3 if you go for bigger species. Better to plant slightly generously and fill in the following year than to jam it full straight away.
Step 7: mulching and watering
Lay a 3 to 5 cm layer of wood chip, bark or coarse compost between the plants. It makes a real difference to drying out and keeps the weeds down. Not up against the stems, and not up against your wall.
For the first six to eight weeks, watering is the difference between a pavement garden and a strip of dead stems. Water generously once every two to three days (a 10 litre can per two metres) rather than a little every day. Deep watering drives the roots downwards; shallow sprinkling keeps them near the surface, where things dry out fastest.
Choosing plants: what genuinely survives there?
A pavement garden is not an ordinary border. It is one of the toughest positions there is:
- Dry. The wall keeps the rain off (rain shadow), and a 45 cm strip dries out at speed
- Hot. Brickwork and paving radiate heat back
- Poor. Whatever you put in is the only decent soil there is
- Draughty. There is often wind running along a wall
- Salty in winter. De-icing salt off the pavement washes into your strip
- Dogs. Corners and posts especially
So pick tough plants. This lot works:
Sunny wall (south and west)
| Plant | Botanical name | Height | Why it copes here |
|---|---|---|---|
| Catmint | Nepeta faassenii | 40-60 cm | Flowers for months, drought tolerant, insects love it |
| Lavender | Lavandula angustifolia | 40-60 cm | Likes hot and dry, stays compact with an annual trim |
| Hardy geranium | Geranium (various) | 30-50 cm | Fills space quickly, very little maintenance |
| Sedum | Hylotelephium (Sedum) spectabile | 40-50 cm | Stores moisture in its leaves, flowers late |
| Ornamental sage | Salvia nemorosa | 40-60 cm | Strong performer, cut back after the first flush and it comes again |
| Yarrow | Achillea millefolium | 50-70 cm | Grows in poor soil, flat flower heads |
| Lady’s mantle | Alchemilla mollis | 30-50 cm | Takes sun and part shade, covers the ground |
| Biting stonecrop | Sedum acre | 5-10 cm | Ground cover for the edges |
Shady wall (north and east)
This is the hardest combination: shade and drought together. These species will take it:
| Plant | Botanical name | Height | Why it copes here |
|---|---|---|---|
| Big-root geranium | Geranium macrorrhizum | 25-40 cm | The champion of dry shade, smothers everything |
| Barrenwort | Epimedium | 25-35 cm | Tough, evergreen foliage on many varieties |
| Hellebore | Helleborus | 30-40 cm | Flowers in winter, when nothing else is out |
| Hart’s tongue fern | Asplenium scolopendrium | 30-50 cm | Grows naturally on old walls, likes lime |
| Male fern | Dryopteris filix-mas | 60-90 cm | Big, sturdy fern that asks for very little |
| White wood aster | Aster divaricatus | 40-60 cm | Flowers in autumn, and does it in shade |
| Lilyturf | Liriope muscari | 30-40 cm | Grassy, evergreen, purple flower spikes |
| Foxglove | Digitalis purpurea | 80-120 cm | Native, self-seeds. Note: poisonous |
| Bugle | Ajuga reptans | 10-20 cm | Ground cover with blue flowers |
| Climbing hydrangea | Hydrangea anomala petiolaris | Climbs | Self-clinging climber that does well on a north wall |
About foxgloves and poisonous plants: foxglove is beautiful and native, but poisonous if eaten. If your pavement garden is on a busy spot where children play, or you have small children who put everything in their mouths, choose something else. The same goes for hellebore.
What to steer clear of
- Bamboo. Runs under the pavement and comes up three houses along
- Big thorny shrubs. Banned along a footway almost everywhere, and rightly so
- Trees. Roots and pavements do not mix
- Bedding plants as the main event. Lovely for one summer, after which you have an empty strip. Use them at most as filler between perennials
- Hydrangeas on a sunny south wall. They want far too much water for a 45 cm strip
Add bulbs: the cheapest improvement there is
Push a handful of bulbs in between your perennials in October or November. By March, when the perennials are not yet above ground, your pavement garden is already green and colourful. Crocus, species tulips, snowdrops and grape hyacinth all do well and come back for years. Cost: a few euros for a hundred bulbs.
Climbers against the wall: allowed, and will it cost you your pointing?
This is the question I get most, and the answer has some nuance to it.
The heart of it: if your pointing is sound at the moment of planting and made with cement mortar, a self-clinging climber does no extra damage. If your pointing is already loose, or it is old brickwork in lime mortar, that is a different story. The aerial roots then work into the soft lime and make existing damage worse. So on an old building or a listed one the rule is simple: get the pointing assessed and repaired if needed first, and only plant after that. Or go for a climber on a wire system.
There is another reason for a wire system: self-clingers have a habit of letting go under their own weight as they get older. A simple stainless steel wire system about 15 cm off the wall catches that, keeps the wall reachable for maintenance and lets air pass behind the plant.
| Type | Examples | Support needed? | Watch out for |
|---|---|---|---|
| Aerial roots | Ivy (Hedera helix), climbing hydrangea (Hydrangea petiolaris) | No | Not on loose or lime-pointed brickwork. Keep it below the gutter |
| Adhesive pads | Boston ivy (Parthenocissus tricuspidata), Virginia creeper (P. quinquefolia) | No | Grows fast, will creep under roof tiles if you let it go |
| Twining leaf stalks | Clematis | Yes, wire or mesh | Keep the roots in shade, the head in sun |
| Twiners | Honeysuckle (Lonicera), wisteria, hops | Yes, strong wire or poles | Wisteria gets heavy and powerful; never let it twine around a downpipe or gutter |
| Tied in | Climbing rose, espaliered pear | Yes, plus soft ties | Needs work every year |
| No climbing organs | Thicket creeper, Parthenocissus inserta | Yes | Often confused with the self-clinging species |
Four practical rules for climbers on a wall:
- Prune at least once a year, and keep the plant below the gutter and away from roof tiles, window frames and vents
- Do not plant it hard against the wall. Put the rootball 20 to 30 cm out and train the shoots back towards the brickwork. The soil is less dry out there
- Think about maintaining your wall. If it needs painting or repointing in five years, choose a wire system you can hinge out or take down
- Ivy attracts insects and birds (it flowers very late in the season, when there is little else about). All good, but it also draws dust and spiders towards your window. Keep it away from bedroom windows if you are sensitive to that
The seven mistakes I see most often
- Soil higher than the perpends. The most expensive mistake in this whole article. See the section on damp
- Nothing but summer flowers. From November to April you are then looking at bare soil. Make sure you have at least two evergreens (barrenwort, lilyturf, hart’s tongue fern, ivy) and some bulbs
- Too many plants in too little space. What is a small pot at the nursery is half a metre across in two years
- Leaving the bedding sand in. Your plants are effectively sitting in a box of sand with a dressing of soil on top. They survive the first year and then they are gone
- No mulch. Without a mulch layer the top layer dries out within a day and the weeds pile in
- De-icing salt on the pavement. In winter use sand or grit on your own stretch of footway, or sweep the snow off your pavement garden rather than into it
- Forgetting to water in the first year. Perennials are only drought tolerant once they have rooted in. That takes one full growing season
What does a pavement garden cost?
Milieu Centraal puts a standard pavement garden of 50 by 200 cm at around 80 euros, including topsoil and native plants. That matches what I see in practice. Below is a realistic range for a strip of six metres by 45 cm:
| Item | Range |
|---|---|
| Topsoil (approx. 0.7 m³, bags or bulk bag) | 40 – 90 euros |
| Perennials (20-30 in 9cm or 1 litre pots) | 60 – 180 euros |
| Mulch (wood chip or bark, approx. 100 litres) | 10 – 25 euros |
| Bulbs (optional, 100 of them) | 15 – 35 euros |
| Edging or kerb slabs (optional) | 0 – 50 euros |
| Climber with wire system (optional) | 40 – 120 euros |
| Total, excluding the optional items | 110 – 295 euros |
How to do it cheaper:
- Ask your council first. Plenty of councils supply free topsoil, collect slabs and sand for nothing, or hand out plants in exchange for paving (in the Netherlands this runs through campaigns like Operatie Steenbreek, and dozens of councils run similar schemes; in the UK, look for greening or “grey to green” grants and the RHS Greening Grey Britain campaign)
- Do it together with the neighbours. One bulk bag of soil shared between three houses is half the price of loose bags
- Buy small sizes. A 9cm pot is a third of the price of a 2 litre pot and has caught it up a year later
- Split and share. Hardy geranium, lady’s mantle and barrenwort can be divided into four after two years. That doubles your garden for nothing
- Look out for plant swaps in your area, often in spring
Maintenance through the year
| Period | What you do |
|---|---|
| March | Cut back last year’s spent stems, top up the mulch, pull the first weeds |
| April – May | Fill in with extra plants if needed, tie in or train the climber |
| June – August | Water in dry spells (a good soak twice a week, not a little every day). Deadhead for a second flush |
| September | Order bulbs, lift and divide plants |
| October – November | Plant the bulbs, top up the mulch layer for winter |
| December – February | Leave the stems standing; insects overwinter in them and you have something to look at. Only clear away what hangs over the pavement |
Two things that apply all year round: keep the footway clear (that is the deal you made with your council, and it is the number one reason a pavement garden gets taken out), and water the soil, not the wall.
What do you do with the slabs?
Seven metres of pavement garden soon adds up to thirty or forty paving slabs. They are heavy and you cannot just put them out with the bulky waste.
- Tell your council. Many councils collect slabs from a pavement garden for free, or take them at the tip
- Put them on the scoreboard. In the Netherlands there is a national tile-flipping championship (NK Tegelwippen) where councils compete against each other, so lifted slabs count towards the local tally. Ask whether your area runs a depaving or greening campaign, and your Saturday works twice
- Reuse them yourself. As a base under a shed, as edging, as a slab path to your back door or as a stand for a water butt
- List them on a classifieds site. Used paving slabs are in demand with people laying a path
Frequently asked questions
Do I need permission for a pavement garden?
In most places you do not need planning permission, provided you stay within the conditions (width, digging depth, clear footway). Many councils do ask for a notification or a short application first, since the pavement is highway land. If you rent, you also need your landlord’s consent. Listed buildings and conservation areas have their own rules, so give the council a ring in that case.
How wide and how deep can a pavement garden be?
Most councils allow 30 to 60 cm wide, which is one to two paving slabs, and require a clear footway to be left. UK guidance points to a minimum of 1.5 m clear width, with 2 m preferred; Dutch councils generally work to 1.2 m. Digging depth is often between 25 and 45 cm, and some councils specify a minimum of 30 cm so the plants have enough soil. Always check the exact figures for your area, because they genuinely differ.
Will a pavement garden give me damp in my wall?
Not from the plants themselves, but it can from a bad build. Two things decide it: never lay the soil higher than the open perpends and airbricks at the bottom of the wall, and give the ground a slight fall away from the brickwork. Do that and a pavement garden behaves no differently from an ordinary border against a house. If you can already see damp patches low down in that wall, sort those out first.
Do climbers damage my wall?
On sound brickwork pointed with cement mortar, a self-clinging climber does no extra damage. On old brickwork in lime mortar, or where the pointing is already loose, it does: the aerial roots work into the soft mortar and make existing damage worse. Repoint first in that case, or choose a climber on a wire system about 15 cm off the wall. In every case keep climbers away from the gutter, roof tiles and vents, and prune at least once a year.
Which plants survive a dry, shady wall?
Big-root geranium (Geranium macrorrhizum), barrenwort (Epimedium), hellebore (Helleborus), hart’s tongue fern (Asplenium scolopendrium), white wood aster (Aster divaricatus) and lilyturf (Liriope muscari) are the most reliable choices for dry shade. If you want to climb a north wall: climbing hydrangea or ivy.
What does a pavement garden cost and how long does it take?
For a two metre strip you come out at around 80 euros, for six metres roughly 110 to 300 euros depending on how many plants you buy and how big they are. Reckon on half a day to a full day of work. Always check with your council first: many supply free soil, collect slabs or hand out plants in exchange for paving.
Who is liable if somebody trips over my pavement garden?
That is exactly why those measurements are in the council’s rules. Stick to the width you were given, leave the required clear footway, put up no fencing and cut back overhanging growth in good time, and you have done what is expected of you. Let your garden sprawl across the pavement and the council can remove it, and you can indeed be held responsible for any injury. And never dig deeper than allowed: hit a cable and the bill is yours.
To finish
A pavement garden is the cheapest job with the biggest visible effect that I know of. For the price of a night out and one Saturday of work, the look of your house changes, and usually within two years so does the look of your whole street, because pavement gardens are contagious.
Get three things right and the rest follows: actually dig the bedding sand out, keep the soil below your perpends, and water it through the first year. The plants do the rest themselves.
Once you get going on greening up around the house, chances are you will start thinking about a planter, a bench against the wall, a housing for the water butt or a window box as well. For that sort of project I have complete plans with cut lists ready to go, so you buy the right sizes and the right timber in one trip. Have a look here: Fred’s DIY Plans
Cheers from Fred Schouten, handyman and DIYer through and through
PS: give your council a ring before you start, even if you cannot find anything on the website. Nine times out of ten you get not just permission, but free topsoil and a date for someone to come and take your slabs away. Saves you half a day of lugging.