Rhododendron 'Shilsonii' (Shilsonii Rhododendron)
Botanical Information
| Family | Ericaceae |
| Genus | Rhododendron |
| Cultivar | 'Shilsonii' |
| Category | Woody |
| Type | Tree (evergreen), Shrub (evergreen) |
| Origin | Parentage: Rhododendron barbatum × Rhododendron thomsonii. |
Details
| USDA Hardiness Zone | 6 - 8 |
| USDA Hardiness Ref. | |
| Canadian Hardiness Zone | 6a - 8a |
| Canada Hardiness Ref. | |
| RHS Hardiness Zone | H4 - H7 |
| RHS Hardiness Ref. | |
| Temperature (°C) | -23 -(-7) |
| Temperature (°F) | -10 - 20 |
| Height | 3 - 4 m |
| Flowering Period | April |
Description and Growing Information
| General Description | Rhododendron 'Shilsonii' is grown for its attractive flowers and evergreen foliage. |
| Shape | Large, open-branched shrubs or small trees |
| Landscape | An excellent addition to winter landscapes, woodland margins, foundation plantings, shade gardens, mixed borders, mass planting, and shrub borders. Use for mass or group plantings or as a specimen plant. |
| Propagation | Grafting and layering, take short cuttings of mature new growth. Place in well drained moist soil, keep in high humidity and indirect light. |
| Cultivation | Best grown in well drained acidic soil with the pH range of 4-6 and partial sun; mulch will assist greatly in retaining moisture so roots will not dry out. |
| Pests | Susceptible to many pests such as aphids, caterpillars, nematodes, scale, lace bugs, mealy bugs, borers, and white fly. Diseases include crown rot, leaf gall, rust, powdery mildew, blights, root rot, and leaf spot. Resistant to deer and rabbits. |
| Notable Specimens | Trengwainton Garden, Madron, near Penzance, Cornwall, United Kingdom. |
| Bark/Stem Description | An exfoliating bark that is pale and waxy as it ages, curling up to expose mahogany red under-bark. |
| Leaf Description | Broad, elliptic, bright green leaves with down-turned margins, and are up to about 15 cm long. |
| Flower Description | 1-4 per cluster, blood-red flowers. |
Photographs
Rhododendron 'Shilsonii', form, Trengwainton Garden, Madron, near Penzance, Cornwall, United Kingdom.
Rhododendron 'Shilsonii', leaf, Trengwainton Garden, Madron, near Penzance, Cornwall, United Kingdom.
Rhododendron 'Shilsonii', bark, Trengwainton Garden, Madron, near Penzance, Cornwall, United Kingdom.