Garden troughs didn't begin life in the garden. At first, the porous stone containers were used in England for watering and feeding animals. But in the late nineteenth century, they became popular containers for plants, and the aged stone beautifully complemented the traditional English garden, especially when planted with miniature alpine landscapes. Extremely heavy, these troughs were customarily set down in a good spot and left in place to gather moss and compliments.
These days, old stone troughs are hard to find, and they can cost up to several thousand dollars. New troughs made from cement mixtures can be found for much less, ranging in price from less than fifty to several hundred dollars, but they, too, are quite heavy.
It is possible, though, to make a lightweight trough, which appears to have been chipped from stone, for less than $20. These troughs use simple molds and a casting mixture of cement, peat moss, and horticultural perlite. The peat moss used in the troughs makes them very inviting to mosses, algae, and lichens that float through the air in search of receptive surfaces. Because the troughs are porous, they are especially hospitable for plants that require good drainage, but they can be used for anything. Irregular shapes and rough edges only enhance the natural-looking qualities that make these troughs so desirable.
These porous troughs are particularly suited to alpine dioramas, because the alpine plants -- including artemesia, allium, draba, and dozens of other small varieties -- typically thrive where there is good drainage and loose soil. Alpine purists often create little worlds with porous stones, gravel, and tiny plants. The troughs can also be used for larger, spreading plants, such as creeping thyme, annuals, and herbs.
Tools and Materials
- Horticultural perlite
- Peat moss
- Portland cement
- Plastic tub (for mixing ingredients)
- Surgical mask
- Drop cloth
- 2 cardboard boxes (one slightly smaller than the other)
- Wooden dowels
- Chicken wire
- Mason's trowel
Garden Trough How-To
1. Make a basic mixture of three parts perlite, three parts peat moss, and two parts Portland cement in a plastic tub. Work with a drop cloth, because making cement can be messy, and wear a mask to avoid breathing in harmful cement dust.
2. When forming the cement and pouring it into the molds, always wear work gloves. Mix the dry ingredients together with enough water to form a cement that is the consistency of moist cottage cheese. The mix will appear darker in this form than it will when it dries.
3. To pour the bottom of the trough, place a cardboard box on the drop cloth with the opening facing up. Any tape, seams, or gouges in the cardboard will appear on the finished trough, so be sure the inside surface of the box is to your liking (keeping in mind that some rough textures are desirable). To make the bottom of the trough, pour in a 1-inch layer of cement. Cut 3/4-inch mesh chicken wire to the same shape as the box, but 1 inch smaller on all sides. Place it on top of the first layer of wet cement for reinforcement. Then top this with another 1-inch layer of cement. Lightly smooth the surface to make it even.
4. To create drainage holes, push several wooden dowels, each about 4 inches long and at least 1/4 inch in diameter, into the middle of the cement, spaced 3 or 4 inches apart. They will be removed later.
5. To reinforce the walls of the trough, fold the flaps of the smaller box inward, and tape them flush against the insides. Place the box upside down on the cement inside the larger box. Center a layer of chicken wire between the inside and outside edges of the 2 boxes. The wire should be 1 inch shorter than the mold so that it will not poke through the top of the finished trough.
6. Use a mason's trowel to fill the mold with cement. Push a wide stick into the wet cement periodically to tamp it down and eliminate any air pockets.
7. Smooth the top edges of the cement with a trowel. Cover the mold with a plastic sheet so that it remains moist while the cement sets. Let the trough cure for up to 6 weeks but no less than 5 days. Once the cement is set, rip out the inner box, remove the dowels, and tear away the outer cardboard. Apart from developing an occasional crack or pit, which might enhance its aged look, the trough can last for years. Make repairs by applying a new batch of cement to the damaged area with a trowel.