It is so much fun to choose which plants you’d like to grow when you are planning to create your own rock garden.
Once you have the stones arranged and the soil properly prepared, all you have to do is choose and find the plants for it.
Choosing your plants
Catalogues and garden centres list alpine and rock garden plants as “plants for rock gardens, stone walls and ground covers.” Most growers don’t distinguish between alpine and rock garden plants because both groups have similar and overlapping characteristics.
Annuals for rock gardens
In addition to low-growing perennials, a rock garden can include small shrubs, dwarf conifers, ornamental grasses and even some well-chosen, suitably discreet annuals. The best options are low-growing or spreading species or cultivars with a similar habit to alpine plants and species with small, downy, blue-green or grey foliage.
Useful annual species include sweet alyssum, California poppies, gazanias and portulaca.
You may also find some alpine species that are normally perennial but are grown here as annuals – pinks, poppies, bellflowers and penny-cress, for instance. They are also well suited to rock gardens and will give you even more to choose from.
Annuals are grown in modern gardens as a way of adding colour. If you decide to use them in an alpine garden, be careful not to spread them around or to plant too many of them. It is best to go for a simple muted look, with splashes of colour dotted throughout.
“Real” rock garden plants
The challenge in creating an alpine garden is to combine alpine and rock garden plants in an appealing manner. It is important not to give into the temptation to plant everything you find. It is better to start with some easy-to-grow species (see the selection table) and get them permanently established in your rock garden before trying your luck with other, harder-to-grow specimens.
For the most attractive site, the perennials you choose for your rock garden must meet certain criteria:
- The “ideal” plant will bloom for an extended period of time, although in this case everything is relative, because plants flower profusely but only briefly in the mountains.
- It is best to choose a dwarf, ground hugging or spreading plant with foliage that stays attractive for much of the year.
- The plant must be able to survive severe winters and hot summers, both of which often cause gardeners to lose their alpine plants.
- The plant shouldn’t require any special care, or at least not too much, and should be available locally. This should be your number one consideration before you draw up your final shopping list.
Based on an article by René Giguère in Quatre-Temps magazine, Vol. 22, No. 1.