In the kitchen gardens and roadside verges of virtually every temperate region on Earth, grows one of the most recognizable aromatic plants—Bo He, mint. The genus Mentha includes dozens of species distributed worldwide, and Chinese medicine has made specific use of the native Chinese species Mentha haplocalyx, known as Bo He, for over two thousand years. The name itself—薄荷—evokes the plant’s characteristic cool, fresh fragrance that creates an immediate sensation of alertness and clarity.
While the West uses mint primarily as a culinary herb and breath freshener, Chinese medicine recognized a plant with powerful therapeutic properties: “dispelling wind-heat, clearing the head and eyes, relieving itching, and promoting eruptions.” For conditions where summer heat or wind-heat had invaded the body creating fever, headache, red eyes, and sore throat, Bo He was the primary remedy. These same properties make it invaluable for incense—the cool, sharp fragrance addressing heat and congestion in ways that heavier materials cannot.
What Is Bo He
Bo He refers to Mentha haplocalyx, a specific species of mint native to China (different from the peppermint and spearmint familiar to Western users, though closely related). The entire plant is aromatic—the leaves, stems, and flowers all contain the menthol-rich volatile oils that give mint its characteristic cooling sensation and sharp fragrance.
Harvesting occurs when the plant flowers in summer—the volatile compounds concentrate at peak levels before the plant’s energy shifts to seed production. The fresh leaves can be used immediately, or dried for longer storage and later use.
《神农本草经》记载：「薄荷味辛凉，主贼风伤寒头痛，恶气，腹胀满，止汗。」
The Divine Farmer’s Classic of Materia Medica records: “Bo He—flavor acrid and cool—governs thief-wind damaging cold, headache, malign qi, abdominal distention and fullness, stops sweating.”
The “Cooling” Sensation
What distinguishes Bo He from other aromatic herbs is the immediate physical sensation:
Menthol activation: The menthol in mint activates the TRPM8 receptors in the skin and mucous membranes—the same receptors that respond to actual cold temperature. This creates the subjective sensation of coolness that mint produces regardless of actual temperature.
Head and eye clarity: The immediate effect on the head—relieving headache, clearing red eyes, opening nasal passages—makes Bo He specific for “wind-heat” conditions affecting the upper body.
Superficial action: Unlike herbs that work deeply in the body, Bo He works on the surface—dispersing wind-heat from the skin and mucous membranes, the entry points where external pathogens invade.
Fragrance Profile
Bo He has the most immediately recognizable aromatic character of any herb:
Primary notes: Sharp, cool, menthol-rich with a distinctive freshness. The fragrance creates immediate sensation of alertness and clarity.
When burning: The smoke carries a sharp, cooling fragrance that many find immediately clarifying. The menthol content means the sensation of coolness persists even in smoke.
Space effect: Even small amounts of burning Bo He create an impression of coolness and clarity in spaces—particularly effective for hot, stuffy, or stagnant environments.
TCM Properties
Bo He’s applications follow from its cooling, dispersing nature:
Wind-Heat Invasion
The primary application addresses external wind-heat invasion:
- Fever that worsens when exposed to heat
- Headache, particularly frontal and worse with heat
- Red, itchy, or painful eyes
- Sore throat and swollen tonsils
- Nasal congestion with thick yellow discharge
Heat in the Head
The “clearing the head” property addresses:
- Headache from heat rising
- Dizziness from liver heat affecting the head
- Mental confusion from heat disturbing the spirit
Skin Conditions
The “promoting eruptions” property addresses:
- Rashes and itching from heat in the blood
- Early-stage rashes that need to “erupt” to resolve
- Heat-type skin irritations
Incense Applications
Bo He serves specific incense purposes:
Heat Relief
The most direct application addresses summer heat:
Burning Bo He creates a cooling sensation in hot environments. The menthol in the smoke produces the subjective feeling of coolness even when actual temperature hasn’t changed—providing relief from the discomfort of summer heat.
Mental Alertness
The immediate clarity-making property serves work and study:
The sharp, cool fragrance produces immediate alertness and mental clarity. Burning Bo He before demanding mental work provides a natural stimulant effect without caffeine’s subsequent crash.
Clearing Spaces
The dispersing quality refreshes stagnant spaces:
Hot, stuffy rooms, spaces after illness, anywhere the air feels heavy or contaminated—the sharp fragrance of Bo He clears and refreshes. Traditional use for “clearing miasma” reflects this property.
Respiratory Support
The head-clearing property benefits breathing:
Burning Bo He during head cold or sinus congestion creates aromatic support for clearing the respiratory passages. The menthol helps open nasal passages and ease breathing.
Blending Component
Bo He contributes to formulations:
Its sharp, cool quality balances heavier materials. A small amount of Bo He in otherwise warming blends creates balance—the cooling quality preventing excessive warmth.
Preparation for Incense
Bo He can be prepared several ways:
Direct burning: Dried leaves and stems burn on charcoal, releasing the sharp, cooling fragrance. The herb burns relatively quickly.
Essential oil: A few drops of peppermint or menthol oil on charcoal provides intense Bo He fragrance. This is very concentrated—use sparingly.
Powder form: Ground dried Bo He mixes with binding agents for incense stick production.
Quality Considerations
Menthol content: Higher menthol content means stronger fragrance and cooling effect. Quality Bo He should produce a strong, immediate cooling sensation when crushed.
Color: Properly dried Bo He retains the green color. Brown or yellowed material suggests age or improper storage.
Fragrance intensity: Crushing a small amount between fingers should release immediate, strong fragrance. Faint smell indicates old or low-quality material.
Source: While Bo He grows widely, Chinese production from specific regions carries traditional reputation for quality.
Modern Research
Modern science has investigated Bo He:
TRPM8 activation: Menthol’s cooling effect works through the same receptors that detect actual cold—this explains the immediate sensation of coolness from mint.
Nasal decongestion: Menthol creates subjective sensation of clearer breathing even when actual nasal passages haven’t opened—useful for cold symptoms.
Antimicrobial: Mint oil demonstrates broad antimicrobial activity—the traditional use for “clearing miasma” has modern scientific support.
Mental alertness: Studies confirm that menthol fragrance improves alertness and cognitive performance—the traditional use for “clearing the head” is validated.
FAQ: Bo He
What does Bo He incense smell like?
Bo He has the sharp, cool, immediate fragrance of mint—the most recognizable aromatic sensation. The menthol content creates a sensation of coolness even when the actual temperature hasn’t changed. The fragrance is alerting and clarifying rather than warming or calming.
Is Bo He safe for everyone?
Bo He is generally safe for most people. The cooling quality means it should be used moderately by people with cold patterns (pale complexion, aversion to cold, diarrhea from cold)—excessive cooling can create imbalance in already cold individuals. Some people are sensitive to menthol and may experience irritation.
Can I use culinary mint for incense?
Yes. Peppermint and spearmint from grocery stores are closely related to the Bo He used in Chinese medicine and work for incense purposes. Fresh herbs are more aromatic than dried; dried culinary mint is less potent than properly processed medicinal Bo He but functional.
How does Bo He compare to other clearing herbs?
Bo He is the sharpest and most immediate of the clearing herbs. While herbs like Ju Hua (chrysanthemum) clear heat more gradually, Bo He produces immediate sensation of coolness and clarity. Bo He works more on the surface; Ju Hua works more on the liver and eyes. They are often combined for comprehensive heat-clearing.
Can Bo He help with headaches?
Yes, particularly headaches from wind-heat or liver heat rising. The immediate cooling sensation provides relief from headache. For other headache patterns (blood deficiency, cold invasion), different treatment approaches would be more appropriate.