Although traditionally used for alpine gardens, sinks are suitable for many other shallow-rooting plants and can add a rustic look when placed in a sunny outdoor corner.
This method is designed to be used on an old white glazed sink but can also be used to create a similar effect with a large wooden fruit crate as the base. Remove any inner partitions to leave a basic box shape then cover this inside and out with chicken wire.
Use a thicker mix of cement to cover the wire on both sides and form solid walls to the container. Before the concrete mix dries make holes in the base for drainage. Drying can take from one day to a week. When planting the container make sure that the surface of the potting mix hides the inside edge of the covering.
Mix for Covering
- Use cement 5 parts by volume to 1 part sand and 2 parts moistened coarse brown peat moss, sieved first to remove any lumps. Add water carefully to produce a sticky mix that is not wet enough to drip.
- Press the mix firmly onto the surface. Don’t worry about making a perfectly smooth finish as a ‘rustic’ look is very attractive.
- Deaden the sheen on the surface with a sander on an electric drill or a wire brush. For safety, wear a protective face mask.
- Clean and dry the surface, then paint with an L even layer of strong contact adhesive, covering the outside and I Ocm (4 inches) down on the inside.
- Mix up some cement as described left, then press it firming on to the tack y sink surface to a depth of about 1-2cm.
- After covering with cement, leave the sink to dry in a frost-free place. When it is completely dry, expose to rain to weather it.
Suitable Sinks
Old sinks provide excellent plant containers as they are deep enough to take the roots of a wide range of plants, and have ready-made drainage.
Ready to use alpine troughs made from reconstituted stone or lighter glass fiber are available from most garden centers. You can also use old kitchen sinks. Those made of stone with unglazed pie-crust edges are very beautiful but have become difficult to find. An alternative is to use a large, white glazed sink and cover the outside with a cement mixture that creates a similar finish.
Positioning
One sink can be used as a miniature garden on its own, while two or three, grouped and raised to different levels, can look very decorative. It is a good idea to raise sinks off the ground to ensure good drainage. They also tend to look more effective mounted on a plinth. You can simply use four bricks, one at each corner, or build short legs or a central plinth from bricks or concrete blocks. Take care not to block the drainage hole.
The Right Growing Medium
Sink gardens need good drainage. Use a 10cm (4 inches) layer of small pebbles, crocks or clay pellets at the bottom and a well-draining potting medium, especially for alpines. Some alpines prefer a mixture with added lime which can be added as crushed limestone. For those that dislike lime use a mixture of peat and sand.
Suitable Plants
Apart from a mixed alpine garden, consider planting a sink with Primulas or Pansies and small bulbs for a winter display. Alternatively, a herb garden containing the smaller herbs like Thyme, Parsley, Chives and Winter Savory could be both decorative and useful.
Create a fern garden for a shady spot or leave the plug in, fill with water and create a miniature water garden, with a tiny Water Lily and a variety of lush, leafy marginal
Lay small pieces of rubble or broken pot around the exit hole to ensure good drainage, then add a 5-10cm (2-4 inches) layer of coarse shingle, small pebbles or clay pellets. On top of this place a thin 2cm (3/4 inches) layer of peat.
Make up an equal-parts mix of soil-based compost and coarse sand or perlite. Add any special requirements for plants preferring an acid or alkali base. Half fill the container and position plants until you find an arrangement you like. Then fill in with the rest of the potting mixture, placing plants according to root depth. Finish off with two or three decorative rocks among the plants and some fine gravel. Water well with a fine rose.
Siting the Sink Garden
Give the siting of your sink garden some serious thought, as it will be too heavy to move afterwards. Make sure that it is in a position which receives adequate sunlight or shade, depending on the plants’ needs. Plants with varying requirements can be planted in their own pots in the sink garden and moved if necessary.
Plants for a Sink Garden
- Aethionema ‘Warley Rose’ is bushy with small grey-green leaves and masses of bright pink flowers in short spikes.
- Armeria caespitosa, the tiniest Thrift, makes a tight mat. It has pink flowers.
- Aubretia deltiodea is also mat-terming with flowers of lilac, purple, red or pink.
- Dryas octopetala is a creeping plant to position near the edge. It has white flowers in late spring followed by dully seed heads.
- Sempervivum arachnoideum forms a tight mat and has deep pink flowers.
- Campanula carpatica comes in blue, purple and white and has small, rounded leaves. It can quickly form large clumps.
- Cassiope has moss-like growth with c h ite, hell-shaped flowers in late spring.
- Primulas and Primroses, in a wide range of colors, will flower through much of winter as well as spring.
- Veronica rupestris has creeping stems, useful for edging the sink. Flowers are a lovely deep blue.
- Ferns need a rooting depth of over 20cm (6 inches) but, by mixing species with different leaf colours and shapes, they can form a decorative green garden for a shaded spot. Try mixing Maidenhair, Tongue, and Palm Ferns.
- Spreading succulents, with a range of leaf colours and flowers, can add rich tones and texture to a large sink garden.
