FOR VALIDATION :: ¿ Pogostemon wightii Benth. ? :: The Nilgiris :: Jan 29, 2026 · 10:11 AM IST

[Dinesh Valke]

FOR VALIDATION :: ¿ Pogostemon wightii Benth. ? The Nilgiris :: Jan 29, 2026 · 10:11 AM IST Kudimalmund, about 2082 m asl

Regards. Dinesh

[J.M. Garg]

Both are quite close.
Dinesh ji, may decide based on the following differences as per Google AI view:

Pogostemon wightii and Pogostemon speciosus are both aromatic, endemic species of the Lamiaceae family found in the Southern Western Ghats of India. They are similar in appearance and habitat, frequently found in high-altitude Shola forests (around 1,000–2,200m). 

ScienceDirect.com +2

The key differences lie in their habit (size/growth form), specific floral characteristics, and leaf texture. 

Key Differences at a Glance

Feature	Pogostemon wightii Benth.	Pogostemon speciosus Benth.
Growth Habit	Small shrub or herb (sometimes subshrub)	Shrub, up to 2 m tall
Stem/Branching	Quadrangular, strigose (stiff, appressed hairs)	Pilose-hispid (hairy) brown branches
Leaf Features	Densely strigose, 5-6 cm long, ovate	Hirsute, 3-8 cm long, ovate/orbicular, turn black when dry
Inflorescence	4-8 cm long spikes, continuous	Often described as having "bottlebrush" appearance
Stamens	Bearded filaments	Lacks moniliform hairs on filaments
Nutlets	Biconvex to triangular, smooth, brown	Suborbicular, blackish, 1 mm long

Detailed Breakdown

• Pogostemon wightii:
  • Description: A small, delicate shrub or herb, often found along stream sides or in marshy spots within Shola forests.
  • Appearance: Leaves are smaller (5-6 x 3-4 cm) and intensely hairy (strigose).
  • Flowering: Occurs in December-January.
  • Distinctive Feature: Filaments (stamens) are bearded.
• Pogostemon speciosus:
  • Description: A more robust shrub, growing up to 2 meters, common on rocky slopes and degraded areas of the Nilgiri and Anamalai hills.
  • Appearance: Leaves are larger and hairy, with the unique characteristic of turning black when dry.
  • Flowering: Occurs from January to February.
  • Distinctive Feature: Leaves and stem turn blackish when dried, and the stamens are very long, giving a "bottlebrush" appearance. 
    ScienceDirect.com +4

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With regards,
J.M.Garg, 
https://efloraofindia.com/

[Dinesh Valke]

Many thanks Garg ji.

I have suggested my IDs for observations of Pogostemon speciosus and Pogostemon wightii, purely on the basis of their inflorescence.

Among their inflorescence, which appears dense, and whose rachis can be clearly seen?
When comparing the inflorescence of these two species, the visual density and the exposure of the rachis (the central stem of the flower cluster) are two of the most reliable ways to tell them apart in the field.

The "Dense" Species: Pogostemon speciosus

• Appearance: This species is known for its thick, robust spikes.
• Density: The flowers are packed very tightly together. Because the individual flowers (corollas) are larger (~7 mm) and more voluminous, they overlap significantly.
• Rachis Visibility: The rachis is hidden. Because the whorls of flowers are so close together and the hairs on the calyx are long, you generally cannot see the central stem once the plant is in full bloom.

The "Exposed" Species: Pogostemon wightii

• Appearance: This species has more slender, elongated spikes.
• Density: The flower clusters (verticillasters) are often spaced out along the stem rather than being a continuous "wall" of petals.
• Rachis Visibility: The rachis is clearly visible, especially between the lower flower clusters. Because the flowers are smaller (~5 mm) and the hairs are appressed (lying flat), the central axis of the inflorescence is much easier to observe.

Summary Comparison

Feature	Pogostemon speciosus	Pogostemon wightii
Spike Width	Stout and broad	Slender and narrow
Flower Packing	Very dense / Congested	Interrupted / Laxer
Rachis	Concealed by flowers	Visible between clusters

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My suggested ID is Pogostemon wightii Benth.

The 2nd photo in this post shows the rachis between the cluster of flowers.

Garg ji, I hope you agree.

Regards.

Dinesh

[Dinesh Valke]

Hello Garg ji,

My study did not help me OR may have misinterpreted the description !!

At iNaturalist, the ID of this observation got corrected to Pogostemon speciosus var. filiformis V.S.Kumar & B.D.Sharma

Many thanks to Sobiyanaz for correcting the ID ... iNaturalist.

Regards.

Dinesh