There are plenty of great plants to consider for an alpine rock garden.
But when you are getting started with growing alpines, it can be great to have a list of some of the favourites that you can use as a starting point for making your selections.
Any list of the top plants for an alpine rock garden will, of course, be highly selective. But here are some top choices that you should at least consider – whatever sort of alpine garden you are creating and wherever exactly it is located.
A rock garden is a great feature for a garden – typically in a sunny and open spot. Creating this type of habitat will allow you to grow a range of relatively low maintenance plants which come from rocky and mountainous regions, and make the most of areas that may have nutrient poor and/or shallow soils.
So if you have made an alpine rock garden, or are thinking about making one, here are 15 great plants to consider:
Aubretia, also known as purple rock cress, or purple chickweed, is a hardy (H6) mat forming perennial. It is evergreen, and has copious, lovely little pink or purplish flowers in the spring. It will thrive in full sun, in a well drained soil that is alkaline or neutral in pH, but can also tolerate a little partial shade.
There are a wide range of diminutive bellflowers, of Campanula, which are perfect for rock gardens. There are literally hundreds of varied options within this genus. One type of bellflower which I would recommend for a rock garden is Campanula portenschlagiana – wall bellflower. This low growing perennial is a great alpine plant, which is evergreen, forming dense mats of small rounded leaves. Then has pretty violet-blue flowers in the summer. H5 hardy, these are ideal for rock gardens or sunny borders where conditions don’t get too wet in winter.
Alpine varieties of Dianthus, also known as ‘Pinks’ are also ideal for many alpine rock gardens. D. alpinus is another mat forming perennial which bears pretty pink or cerise flowers in the summer months. It is H6 hardy, and will thrive in a well drained position in full sun, with alkaline or neutral pH. Their flowers are vibrant additions to an alpine rockery.
4. Gentiana verna
Spring gentian is another lovely alpine for a rockery. This is another small evergreen mat forming perennial. But in spite of its small size, it can really make a big impact with its stunning sky-blue flowers with white centres, which bloom in late spring and early summer. It is H5 hardy, and prefers a moist but well-drained soil that is alkaline or neutral, in full sun.
5. Geraniums (Alpine varieties)
Alpine geraniums are another notable group of plants to consider for an alpine rock garden. One great example is G. ‘Ballerina’ (Cinereum Group), a great ground cover plant and great for wildlife. It is an H5 hardy herbaceous perennial which forms small clumps of foliage and flowers with pinkish purple hued blooms in late spring/ summer. The evergreen perennial G dalmaticum is another great option to consider for your rock garden.
Lithodora diffusa is a great training plant for the rock garden. H5 hardy, it has deep green foliage that spreads well, and deep gentian blue flowers which bloom over a long period from May through the summer months. It will do best in full sun, in an acid or neutral soil.
Pine-leaved penstemon, P. pinifolius, is another interesting rock garden plant to consider. This bushy dwarf shrub is evergreen, with short, needle leaves. And it bears bright scarlet tubular flowers in the summer months. It will thrive in very well drained, sheltered, spots in full sun. And other Penstemon to consider is P. laetus subsp. Roezlii, a perennial which bears purple flowers from late spring to mid-summer.
8. Pulsatilla vulgaris
Also known as pasqueflower or meadow anemone, this clump forming perennial wows with its large nodding purple flowers, followed by silky fruiting heads. It is H5 hardy and will thrive in any very well drained soil in full sun. Though it can be hard to establish, once it beds in it is wonderful for an impressive alpine rock garden.
Phlox is a genus which offers a number of different mat forming evergreen perennials which work very well in sunny, well-drained rock gardens. They have small pinkish flowers which emerge from late spring. Phlox douglasii and Phlox subulata are both great examples, which are H^ hardy and fairly resilient in the right conditions.
For a moist but well drained rock garden in full sun, ideally in loam, Primula auricula is another reliable choice. This evergreen perennial has lovely bright flowers which emerge in the spring. H5 hardy, these are relatively well known and popular primulas for a rock garden. (Note, these are not the same as true show auriculas. Primula marginata, Primula allionii and their many hybrids are also excellent options for an alpine rock garden.
Saxifraga are yet more mat forming perennials great for adding lush greenery to alpine rock gardens. There are a number of examples with flowers of various different hues. S. ‘Silver Cushion’ and S. paniculata. ‘Lavagreana’, ‘Rosea’ and ‘Venetia’ are all top options to consider, for example, when growing alpine plants. If you are new to alpine rock gardening then this genus should be one of the go-to choices.
Like saxifrages, Sedums are also an obvious go-to choice for rock gardens, whether you are a complete novice or a far more experienced gardener of alpine plants. Many stonecrops, with their pretty little star-shaped flowers, are ideal for nestling among rocks in a rockery, or even planting into the top of a stone wall. S. cauticola, for example, is one top Sedum to consider for an alpine rock garden.
For free draining, sunny sites, succulents like sempervivum are often a great choice. Houseleeks, as they are sometimes called, are very easy to please alpine succulents. There is a reason why they are so well known and widely recognised. With attractive and intricate rosettes, they can grace your garden for many years as long as they don’t have ‘wet feet’ and are protected from excessive rain in winter.
Thyme is a plant that you might be more likely to consider placing in a herb garden rather than in an alpine rock garden. But Thymus vulgaris will be right at home in this location. Well known as a culinary herb, thyme can also be a great decorative plant – producing little purple flowers in addition to the aromatic leaves. A creeping thyme variety will be ideal for spreading through your rock garden.
Veronica prostrata, or rock speedwell, is my final pick – another of my favourites for an alpine rock garden. This mat forming semi-evergreen perennial thrives in well drained locations in full sun. It is H5 hardy and has really pretty blue flowers that bloom during the summer months. This is another relatively easy and low-maintenance alpine plants great for a rock garden.
A rock garden can represent while a big investment in rock, and in time and energy even where the rocks were already available on site. So it is important to make sure that you make the right plant choices for your particular rock garden.
Rock gardens are often considered to be quite challenging as gardens go. But when you carefully choose the right plants, it can be easier than you might think. A well designed alpine rock garden, once established, will require little care.