Grottos, waterfeatures, seating and planter pockets require special attention. In many instances, they serve as focal points in rockscapes and, as such, must not only appear natural, but must be functional as well.
Grottos pose a special challenge because often the temptation is to create clean, highly defined lines. This must be avoided. In nature, a grotto appears as a mass of rough-hewn rock rather than a textured igloo.
To avoid too clean a silhouette, try strategically forming craggy and smooth surfaces using irregular patterns. The grotto should not protrude from the ground at a perpendicular angle. Most varieties of stone gradually rise from the earth with individual rocks occurring at different angles.
When working with GFRC castings, surround the grotto’s entrance with high-relief pieces to enhance the irregularity. Avoid placing the entry in the center of the grotto or creating a perfect arch.
When forming the grotto’s interior, the focus must be shared between the twin goals of realistic depiction and safety. To reduce the risk of end-users getting nicked by the walls, use smooth castings or sculpt level surfaces. This also creates the illusion that the formation was eroded by water. Conversely, the ceiling, which poses no danger of contact and is more difficult to see, can feature exaggerated textures.
Waterfeatures also offer the temptation to design unrealistically regular shapes, and so, with rare exceptions, avoid creating water sheets when working with non-natural rock.
In addition, do not construct a mass and simply spill water over its form. Instead, when designing large, monolithic cliff faces, be sure to recess the stone where the water will fall, as the indentation creates the appearance that the water has eroded the cliff.
When a formation incorporates individual rocks, it’s crucial to place them in an irregular path, leaving the water to meander through a maze of stone rather than straight down.
Though water curtains do occur in nature, perfectly defined glassy sheets do not. For this reason, installers should avoid the razor-sharp weir, often seen on sleek, contemporary projects, that cuts water into a clean, ¼-inch-thick sheet. If a curtain is desired, the weir should be constructed so that it’s bulkier than a shelf. Some advise creating weirs that are at least 6 inches thick.
To provide texture, it’s imperative to blend the weir with the rest of the rock, an effect that can be aided by utilizing authentic rock specimens or pre-manufactured boulders.
Placing a weir at the top of a formation is not recommended, as the result always appears unrealistic. Instead, set it lower down, with a smaller whitewater fall at the approach. Pooling water behind the weir adds realism and helps obscure it.
Seating areas are perhaps the most challenging feature of all, since designers must create a realistic space that also provides a comfortable area for relaxation. The seating should appear to be part of the formation, rather than a highly textured bench.
When designing these areas, artists and installers should carefully envision how they will be used. A larger family may be better served with one location for intimate conversations and another that accommodates three or four people for a different dynamic. Regardless of the scenario, success can be found by using carefully sized rocks to create the seating.
To balance realistic appearance with comfort, some artists combine GFRC and hand sculpting methods. This is accomplished by placing glass fiber reinforced concrete panels at the front of a seating area, then hand sculpting the top with texture skins or foil for a softer relief more conducive for sitting.
Rock also can be formed into a bench-like shape protruding from a larger mass. For this effect to be successful, the bench should gradually blend into the rock formation rather than cantilever outward. Some high-relief GFRC panels come with this protrusion already formed by the manufacturer.
To make a project appear natural, another layer often is needed — softscape. Designers should provide specific areas to set plants while avoiding perfect, and non-natural appearing, bowls. Instead, create a number of rifts that are large enough to accommodate plantings. This gives the appearance that the greenery has grown between cracks in the stone.
Place plants in realistic arrangements. In natural formations, a seed will drop into a large rift crack, where it will grow and expand the opening.
When placing the plants, the soil should be hidden.