Alpines are small shrubs or perennials that grow naturally in mountainous areas and are often used in rockeries. They grow in poor, thin soils with very good drainage. Many are cushion or mat forming and creeping to prevent damage from wind and their fleshy or hair foliage prevents water loss. They do not like damp, humid conditions and like to have their foliage and roots kept dry.
Care: Alpines should be sited in full sun away from trees and in extremely well drained soil, if in doubt, add lots of extra grit. Alpines do very well in sink gardens or raised beds which show off small specimens. Many thrive in cracks between bricks in walls or between paving slaps in pathways.
Pests and Diseases to watch out for:
- Aphids: Treat with a suitable pesticide such as fatty acids
- Birds: Plants may be torn to pieces. Lay lengths of cotton across the plants as a deterrent
- Caterpillars: Remove by hand
- Cutworms: These pests eat through the plant just below soil level. Lift the damaged plant to expose the grub and remove by hand
- Slugs: Can completely devour a plant in one night. Use biological control such as nematodes or buy a prepared solution from your local garden centre
When deciding where to site your rock garden bear in mind the following requirements. Position it in a sunny area away from large trees or shrubs. Any good garden soil will do but it must be gritty and well drained. If yours isn’t, then dig in a good amount of coarse sand and/or stone chippings.
The stone you use for decoration can be any natural, weathered stone but Tufa is also useful. The rocks should be firmly placed in the soil to ensure that don’t move as the plants grow and should look as natural as possible.
If space is limited the best way of growing alpines is in raised beds, sinks or troughs. These can be as small or as big as you want and as long as they have good drainage holes the plants will do well. Place crocks over the drainage holes and add a planting mixture of 2 parts good loam, 1 part of peat or peat substitute, 1 part coarse sand and 1 part of stone chippings.
Allow the soil to settle before planting; planting in groups will give the best affect. Weed regularly by hand, do not feed and water only during dry spells. Each year dress the top of the soil with some of the planting mixture to keep it looking neat and to keep the roots covered.