In Part 1 of this article, the style and choices of rock gardens were explored. In this part of the article, instructions for building a simple rock garden with plants are discussed. Having selected your spot, spread layers of newspaper several sheets thick into the shape you want for your rock garden. If you are making a five foot diameter circular rock bed, measure the newspaper area and make sure it looks big (or small) enough.
Cover the newspaper sheets with a three inch layer of soil and lay a circle of rocks around the outside edge. Keep your rocks under twelve inches on any one side, so that they are not too heavy to lift. Next, fill the circle in with composted soil, adding sand if you have clay soil as most rockery plants like sandy and well drained soil. Stamp it down with your feet to 'pack it down'.
The second layer will be built the same as the first one, but it will be a smaller, inner circle; thus you will have a circle within a circle. These rocks will be more on show, so use the more decorative ones here. Make sure that your second circle is substantially smaller than the first, to give room for plants in some of the 'spaces' of soil between the two layers of rocks. Fill in the center again with soil as before and prepare to plant your rock plants.
Choose plants that like good drainage, e.g. 'Snow-in-Summer' is white bloom with silver leaf and is known as cerstium tomentosum. 'Hens and chicks' have pink/red flowers and the botanical name is Sempervivum tectorum; the foliage comes in different colors. White candytuft is striking (Iberis sempervirens).
For foliage, Scotch moss (Sagina subulata 'Aurea') is a bright green that will brighten the rock colors and lamb's ear (Stachys byzantina) boasts silver foliage. When choosing the plants, stick to the color scheme that you have chosen and always check the label for soil and sunshine requirements.
Buy your chosen plants in groups of three or four to give unison to your rock garden. Add small rocks as you plant the central area, to give the impression of shrubs 'pushing through' rocks. At this stage, some of the rocks can be flat or smooth shaped as well as the jagged shape of the others.
If you want height, add one or two more large rocks in the center of your rock garden. Be sure to add some trailing shrubs in some of the crevices between the rows, a popular one is 'jeepers creepers' (Tiarella) with its varied choice of bloom or golden 'creeping Jenny' (Lysimachia nummularia 'Aurea').
If you want to obliterate weeds, you can mulch - but on a rockery you will need to 'stone mulch'! Sound weird? This is because using bark or wood chips spoils the natural rock effect - so stones it is. Either hunt for your own on the beach, or for a professional effect buy stone mulch to match your rock at the local nursery. Scatter these to completely hide your soil - then step aside and admire your handiwork!