That crunch underfoot
commercial project, we wanted soft-looking, inexpensive paths (miles of them) that could cope with wheelchairs. The solution was to mix a sandy soil with a smallish particle-sized gravel and dry cement. The result was a light, sandy, firm surface (i.e. no loose gravel) that was extremely economical. Soil and cement roads were once common in the States and at airbases in Germany. Apparently, they cultivated the soil, added water, applied the dry cement and mixed the two so they were evenly distributed. They added more water if needed and then raked it smooth. It was left to cure for seven days with no traffic. These tracks looked similar to the colour of the soil, but were hard and did not “dust”. The Japanese method of adding the gravel gives extra texture to the mix, which looks better. Both are ideal for the garden, but alter the proportions and materials to give you a colour and texture you like. A brick or stone edge finishes it nicely. A surface for all seasons: Julie Toll’s garden at RHS Wisley in Surrey shows gravel’s versatility Self-binding gravels Self-binding gravels, such as Breedon gravel (from Breedon Enstone) is one of my favourites (breedon-specialaggregates.co.uk). Selfbinding gravels don’t move like ordinary loose gravel; they are fine textured and have clay particles mixed with the gravel. They are spread (usually to about 50mm depth) over a hardcore base and then rolled with a heavy roller while hosing water over the roller to compact it. The water brings the clay particles to the surface and seals the top. You can ride bikes and wheelchairs over it; even your high heels won’t disappear disastrously into it. My outdoor dining area at home is surfaced with it, and I love it. One of the parking areas at Althorp House is surfaced with it. A few people don’t get on with it though. If you walk from soil to the gravel, bits of earth all over it are difficult to remove and look messy. At home when I am weeding adjacent areas I use tarpaulin to cover it. Weeds cannot be pulled out, as this breaks the surface, so glyphosate is necessary and moss killers will be needed if you don’t like the mossy look. The oldfashioned hoggin is similar, being naturally occurring well-graded gravel with clay particles. You need to find a local source, as transport is usually most of the cost. Perhaps a more forgiving version of this is Cedec (ced. ltd.uk). This is a permeable product (i.e. the rain runs through, not off it) that Michael Heap (who runs CED) developed for public paths around Canary Wharf. The client wanted a durable finish like the boules courts in France. It is a crushed aggregate with a particle size from 6mm. It packs down so it does not drift like loose gravel and is available in yellow/buff, grey and red. It can be laid on slopes up to 1:25. For steeper slopes use SuperCedec, which has a firmer surface. Neither is suitable for regular vehicle use and the cost is from £10 per sq m.