Plant Wiki

The open plant encyclopedia

Know any plant.
Grow it well.

Snap a photo or search by any name to see how to care for it, where it comes from, whether it's safe, and a 3D model you can turn.

  • 13,000+plants with full pages
  • 365,000+plant species worldwide
  • 220+countries covered

Common in

See all

The plants people record most in your country, and ones that grow there wild.

What do you want to do?

Popular plants

Browse all plants

See them in 3D

All plants in 3D

Browse plants

Filter by what you want to do, shape, origin, country, care and safety.

Plant Wiki › Browse plants

King Rhododendron

Rhododendron rex

King Rhododendron
Photo: Daderot, CC0

A tree-sized rhododendron from south-west China, usually 5 to 8 m tall, grown for its creamy to pink bell flowers and large felted leaves. It needs cool, mild, frost-free conditions and shelter from wind and hot sun.

Family
Ericaceae (Heather family)
Grows as
Tree
Light
Part shade
Water
Keep the soil evenly moist, never waterlogged or bone dry, and use rainwater or low-lime water.
Soil
Acidic, humus-rich, free-draining soil with a pH of about 5 to 6.
Temperature
12–22 °C; protect from frost and hot dry winds; hardy to about -10 °C when established
How easy
Hard
Safety
Toxic: All parts, especially leaves and nectar, contain grayanotoxins that can cause vomiting, dizziness and low blood pressure.. Toxic to cats and dogs (ASPCA).
Native range
China (SW. Sichuan, W. & N. Yunnan)
Climate
temperate

About

Rhododendron rex (大王杜鹃), the king rhododendron, is a tree species, usually 5–8 m (16–26 ft) in height, in the family Ericaceae. It is found in China, India, and Myanmar, where it is threatened by habitat loss. The flowers are creamy-white, or pale yellow to pink, with a crimson basal blotch. The leaves are 17–27 cm in length and are covered on the underside with an indumentum that ranges in colour from greyish to rusty brown.

The Royal Horticultural Society describes Rhododendron rex and its subspecies as very large shrubs or trees, reaching 12 m (39 ft) in cultivation. Three of them have received the RHS Award of Garden Merit:-

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 rex 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.

Credits & terms

Identify a plant

Point at a leaf or flower and snap. One plant in frame works best.

Your photo
Starting camera…