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Japanese Azalea

Rhododendron japonicum

Japanese Azalea
Photo: Σ64, CC BY 3.0

Rhododendron japonicum is a deciduous shrub native to Japan, usually 4 to 8 ft tall, grown in gardens and as a bonsai. It needs acidic, well-drained soil and dappled light to flower well.

Family
Ericaceae (Heather family)
Grows as
Tree, Shrub
Light
Part shade, Bright indirect
Water
Keep soil evenly moist, never waterlogged or bone dry, and use rainwater or soft water where possible.
Soil
Acidic, humus-rich, free-draining ericaceous mix.
Temperature
Hardy to about -15 °C; protect pot-grown plants from frost, ideally keep above 5 °C in winter.
How easy
Moderate
Safety
Toxic: All parts of rhododendrons contain grayanotoxins that can cause nausea, vomiting, and low blood pressure if eaten.. Toxic to cats and dogs (ASPCA).
Native range
Japan (Honshu, Shikoku, N. Kyushu)
Climate
temperate

About

Rhododendron japonicum, the Japanese azalea, is a species of flowering plant in the family Ericaceae, native to Japan. A deciduous shrub reaching 8 ft (2.4 m) but usually half that, it is found in grasslands and open scrub, never in dense thickets or woodlands. It is very similar to the Chinese endemic Rhododendron molle, to the extent that its cultivars are customarily grouped with the cultivars of R. molle.

It is popularly cultivated as a bonsai tree.

Other Rhododendron plants

Rhododendron album · Rhododendron anthopogon · Rhododendron argyrophyllum · Rhododendron augustinii · Rhododendron bureavii · Rhododendron calophytum · Rhododendron calostrotum · Bell Flowered Rhododendron · Bent-style rhododendron · Rhodora · Catawba rosebay · Georgian Snow Rose

Text excerpted from the Wikipedia article Rhododendron japonicum by its contributors, under CC BY-SA 4.0; the excerpts and the care summary drawn from them are shared under the same licence.

The care summary was written by AI (Claude, Anthropic) from the sources on this page, with general growing knowledge where they are silent. Check before relying on it.

Life form, climate and native range: World Checklist of Vascular Plants, Royal Botanic Gardens, Kew (CC BY 3.0), reformatted; see Plants of the World Online.

Pet safety from the ASPCA toxic and non-toxic plant lists.

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