Rhododendron maximum
| Rhododendron maximum | |
| Light: |  |
| Moisture: |  |
| Hardiness: | 3 |
| Soil pH: | 5.6-6.5 |
| Evergreen | |
| Height: | 11' |
| Blooms: | Early Summer-Mid Summer |
| Open Woods Forest | |
| Native to: | |
| Medicinal Rating: | |
| Tea: | Yes |
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Rhododendron maximum (common name: rosebay rhododendron)
Propagation: 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[1]. 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[2].
Cuttings of half-ripe wood, August in a frame. Difficult[2].
Cultivation: Succeeds in a most humus-rich lime-free soils except those of a dry arid nature or those that are heavy or clayey[3]. Prefers a peaty or well-drained sandy loam[3]. Succeeds in sun or shade, the warmer the climate the more shade a plant requires[1]. A pH between 4.5 and 5.5 is ideal[3].
Hardy to about -30°c[4].
Succeeds in a woodland though, because of its surface-rooting habit[1], it does not compete well with surface-rooting trees[3]. 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[1].
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[1].
Plants in this genus are notably susceptible to honey fungus[1].
Range: Eastern N. America - Nova Scotia and south to Georgia and Alabama.
Habitat: Damp places along streams, edges of bogs and ponds, woods and mountain slopes to 900 metres[5][4], often forming impenetrable thickets[6].
Medicinal: The poulticed leaves are used to relieve arthritic pain, headaches etc[7][8]. A decoction of the leaves is occasionally employed internally in domestic practice in the treatment of rheumatism[9][10].
The leaves are taken internally in controlled dosage for the treatment of heart ailments[8]. Caution is advised, see the notes above on toxicity.
Usage: Wood - fine-grained, hard, heavy, strong, rather brittle[11][7][9][12]. It weighs 39lb per cubic foot[6]. Used for tool handles and as a boxwood (Buxus spp.) substitute in engraving[11][7][9][12].
Pollinators: ees
Soil: Can grow in light and medium soils.
Drainage: Prefers well drained soil.
In Leaf: Evergreen
Seed Ripens: Mid Fall
Flower Type: Hermaphrodite
Known Hazards: The leaves are poisonous[8]. Ingestion can cause convulsions and coma[8].
The pollen of many if not all species of rhododendrons is also probably toxic, being said to cause intoxication when eaten in large quantities[13].
Also Known As: R. procerum.
Links
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Huxley, Anthony. The New Royal Horticultural Society Dictionary of Gardening. MacMillan Press, 1992.
- ↑ 2.0 2.1 Sheat, Wilfrid. Propagation of Trees, Shrubs and Conifers. St Martin, 1948.
- ↑ 3.0 3.1 3.2 3.3 Chittendon, Fred. RHS Dictionary of Plants. Oxford University Press, 1951.
- ↑ 4.0 4.1 Phillips, Roger and Martyn Rix. Shrubs. Pan Books, 1989.
- ↑ Lyndon, Merritt. Gray's Manual of Botany. American Book Co, 1950.
- ↑ 6.0 6.1 Britton, Nathaniel and Addison Brown. An Illustrated Flora of the Northern United States and Canada. Dover Publications, 1970.
- ↑ 7.0 7.1 7.2 Usher, George. A Dictionary of Plants Used by Man. Constable, 1974.
- ↑ 8.0 8.1 8.2 8.3 Foster, Steven and Billy Tatum. Medicinal Plants of Eastern and Central North America. Houghton Mifflin, 1990.
- ↑ 9.0 9.1 9.2 Sargent, Charles. Manual of the Trees of North America. Dover, 1965.
- ↑ Moerman, Daniel. Native American Ethnobotany. Timber Press, 1998.
- ↑ 11.0 11.1 Uphof, Johannes. Dictionary of Economic Plants. Weinheim, 1959.
- ↑ 12.0 12.1 Elias, Thomas. The Complete Trees of North America. Van Nostrand Reinhold, 1980.
- ↑ Facciola, Stephen. Cornucopia - A Source Book of Edible Plants. Kampong Publications, 1990.