Rockin' the Garden

Plan a
rock garden
that’s a hit

Made to look as though time sculpted the landscape, a rock garden is a classic hit. Part of a rock garden’s appeal is the way it takes care of itself. With nary an annual
in sight, it’s a perennial lover’s paradise. And although it does require some effort and thoughtfulness to compose, a rock garden will provide years of satisfaction with minimal maintenance. A reasonable investment for an ample reward. It’s not hard to understand why this type of garden rocks.

Brilliantly coloured and perfectly poised, a cyclamen’s petals are impossible to resist. Heart-shaped leaves with silver markings add to this plant’s charm. Cyclamen coum is low growing, blooms from late summer to fall and does best in partial shade. Apply deep, loose mulch for winter. 
If you’ve got a natural slope with ample sunlight, you’ve got the perfect place for a rock garden. Here are some tips to get you started.

Getting it Right
Start small. It takes lots of material and energy to create a large rock garden, so start with a bed just over one metre wide and two metres long (4x8). You can pack a lot of plants into a space that size, especially if they’re smaller alpines. It will still be labour intensive, but on a smaller scale.
Prepare the soil properly. Most alpine and rock garden plants need good drainage and, therefore, require gritty soil. To create the perfect mix, add at least one part coarse, sharp sand or finely crushed rock to each part organically rich soil. Supplemental grit can also be added to the planting holes.
Choose the right plants. Rock gardens are primarily comprised of perennial plants that thrive in good drainage. Most contain alpines, other low-growing perennials, dwarf bulbs, dwarf conifers and miniature shrubs. Some of our favourites are profiled in this article.
Place rocks thoughtfully. Combine small, medium and large rocks to create a natural-looking landscape. Seat rocks into the soil by one-third to one-half their width or height—this mimics natural stone outcrops and provides stability. Also place rocks so their grains run parallel to each other. Ideally, cover 20–40 percent of the area with rock, keeping
in mind that a medium-to- large-sized rock will weigh about 45 kg (100 lb).
Top-dress. Top-dressing with crushed limestone or pea gravel isn’t done only for esthetic reasons. It also reduces erosion and compaction, retards evaporation and keeps roots cool. Deep collars of top-dressing around plants are also helpful in preventing what is called winter wet—moisture that sits at a plant’s crown, causing roots to break during freeze-thaw cycles.

Create a container rock garden. A miniature landscape contained within a stone (or faux stone) trough is a lesslabour-intensive way to enjoy rock gardening. Provided your container is placed on the ground, has good drainage andis thoroughly watered before freeze-up, you can successfully overwinter plants—even in colder climates, such as ours. Of course, you will need to be selective with your plant material. Try hens and chicks, low-growing sedum, mountain avens, sandwort, moss campion, alpine willow or miniature spruce.



Alpine Sandwort

Arenaria obtusiloba

Sandworts are eminently popular choices for rock gardens, wall crevices or between paving stones. This one sports white flowers in summer. Mat-forming and evergreen. Avoid winter wet. Height: 10–15 cm; width: 30 cm. Sun.



Gentiana sino-ornata

Dramatic cobalt-blue flowers are what attract people to gentian. This one is also a late-summer to fall bloomer, which makes it a valued addition to a rock garden. Shiny needle-like foliage is semi-evergreen. Height: 5–10 cm; width: 30–40cm. Shade to A.M. sun.


Alpine Thyme

Thymus comosus

No rock garden would be complete without at least one kind of thyme. Pretty pink flowers shine above the greyish foliage of this species. Height: 2–5 cm; width 15–30 cm. Sun to P.M. sun.


Golden Primrose

Vitaliana primuliflora ssp. Praetutiana

Evergreen foliage provides its own stunning show after the bright-yellow spring blooms of this primrose have faded. It has rosettes of grey-green leaves with frosted edges, which arrange themselves into attractive looking cushions. Avoid winter wet. Height: 2–5 cm; width: 15+ cm. Sun to P.M. sun.