Alpenrose
Rhododendron ferrugineum
Family: Ericaceae
What it is like
Rhododendron ferrugineum is an evergreen Shrub growing to 1.5 m (5ft). See above for USDA hardiness. It is hardy to UK zone 4. It is in leaf all year, in flower in June, and the seeds ripen in August. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. Suitable for: light (sandy) and medium (loamy) soils and prefers well-drained soil. Suitable pH: mildly acid soils and can grow in very acid soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.
Height (m): 1.5
Where it is found
Mountain slopes in open woods or scrub, often dominant in the dwarf shrub zone.
Europe.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 0
Medicine
Rating: 1
The flowers, leaves and the galls are antirheumatic, diaphoretic and diuretic. It is used in the treatment of certain forms of arthritis and rheumatism, but can cause diarrhoea and vomiting so should only be used with expert supervision. A homeopathic remedy is made from the plant. It is used in treating a variety of complaints involving flatulence.
Antirheumatic: Treats rheumatism.
Diaphoretic: Induces perspiration.
Diuretic: Acts on the kidneys, promoting the flow of urine.
Homeopathy: A plant used in homeopathic treatments.
Other
Rating:
Plants can be grown as ground cover when spaced about 1 metre apart each way. Some substances in this plant have shown herbicidal activity, though more research needs to be carried out.
Herbicide: Plants or plant extracts that can inhibit the growth of other plants.
Ground cover: Ground Cover
How it is grown
Succeeds in a most humus-rich lime-free soils except those of a dry arid nature or those that are heavy or clayey. Prefers a peaty or well-drained sandy loam. Succeeds in sun or shade, the warmer the climate the more shade a plant requires. A pH between 4.5 and 5.5 is ideal. This species grows better in the midlands and north Britain, disliking the hotter conditions in the south. Succeeds in a woodland though, because of its surface-rooting habit, it does not compete well with surface-rooting trees. Plants need to be kept well weeded, they dislike other plants growing over or into their root system, in particular they grow badly with ground cover plants, herbaceous plants and heathers. Plants form a root ball and are very tolerant of being transplanted, even when quite large, so long as the root ball is kept intact. Plants in this genus are notably susceptible to honey fungus.
Propagating it: Seed - best sown in a greenhouse as soon as it is ripe in the autumn and given artificial light. Alternatively sow the seed in a lightly shaded part of the warm greenhouse in late winter or in a cold greenhouse in April. Surface-sow the seed and do not allow the compost to become dry. Pot up the seedlings when they are large enough to handle and grow on in a greenhouse for at least the first winter. Layering in late July. Takes 15 - 24 months. Cuttings of half-ripe wood, August in a frame. Difficult.
Best place to grow: Woodland Garden Dappled Shade; Shady Edge; Ground Cover;
Habit: Shrub
Hardiness: 4-8
Growth:
Soil: Light (sandy), medium
Shade: Semi-shade, no shade
Moisture: Moist
Things to keep in mind
The leaves and the galls are poisonous. The pollen of many if not all species of rhododendrons is also probably toxic, being said to cause intoxication when eaten in large quantities.