SafePlants

Costus: A Tropical Delight

Costus is a fascinating group of perennial herbaceous plants belonging to the Costaceae family, first described as a genus by Linnaeus in 1753. These plants are native to tropical regions around the globe.

Considerations for Pets

• Some species of Costus, particularly Saussurea lappa, have roots and oils extracted from the roots that possess a very tenacious odor that has been described as reminiscent of old precious wood, wet dog, human hair, or animal fur.
• Costus species are known for their bamboo-like stalks and spiral foliage arrangements, which may present a curiosity for pets.

Considerations for Children

• Costus species are known for their bamboo-like stalks and spiral foliage arrangements, which may present a curiosity for children.

Scientific Name and Common Names

• Scientific Name: Costus (genus)
• Common Names: Spiral Ginger, Insulin Plant (specifically for Costus igneus), Kuth (specifically for Saussurea costus), Mu Xiang (specifically for Costus found in China).

Taxonomy and Nomenclature

• Family: Costaceae
• Major Group: Angiosperms (Flowering Plants)
• Additional Classification: Monocot Herbs
• Synonyms/Related Genera: Mentions Saussurea costus (synonym *Saussurea lappa*) which is in the genus *Saussurea* and the family Asteraceae (Compositae).

Distribution and Habitat

• Widespread throughout tropical regions.
• Specific mentions: South Asia (Saussurea costus), high altitude areas in China, India, Africa, the New World, and Australia.
• Saussurea lappa grows in high valleys in the Kashmir region.

Morphological Characteristics and Growth Habits

• Perennial herbaceous plants.
• Spiral arrangement of leaves on the stems in some species (e.g., Costus dubius).
• Foliage spirals around bamboo-like stalks.
• Some varieties have a velvety soft texture.
• Crepe ginger (a Costus species) can grow to 10 ft (3.1 m) with large dark green leaves arranged spirally.
• Rhizomes are horizontal and tuberous.
• Stems are sometimes branched, usually spirally twisted, leafy, and rarely stemless.
• Leaf blade oblong to lanceolate.

Quirky Facts

• The odor of Costus root oil (from Saussurea lappa) is described as extremely tenacious and reminiscent of old precious wood, but also likened to the smell of wet dog, human hair, or animal fur.

Interactions with Other Organisms

• Mention of use in traditional medicine (implied, "wood aroma")
• Costus igneus leaves are believed to lower blood glucose.