Linden / Tilia
Tilia cordata
Description
overall appearance
A large deciduous tree reaching 20β40 m in height with a broadly domed crown. Has distinctively heart-shaped leaves, highly fragrant creamy-yellow flowers, and smooth gray bark on young trunks becoming furrowed with age. Often planted as a street tree throughout Europe.
roots
Deep, spreading root system with strong taproot and extensive lateral roots; tolerates urban compacted soils; roots may surface on mature trees
stem
Single erect trunk up to 1 m diameter in mature specimens; bark gray-brown, smooth on young trees, developing deep longitudinal furrows; branches spreading and pendulous in mature form
leaves
Alternate, simple, cordate (heart-shaped), 4β8 cm long and wide; apex abruptly acuminate; base oblique; margin finely serrate; dark green and glabrous above, paler below with tufts of reddish-brown hairs in vein axils
flowers
Cream to pale yellow, 5β8 mm wide, strongly fragrant; 5 petals; borne in pendant cymes of 4β15 flowers attached to a distinctive strap-shaped bract 5β8 cm long; blooms JuneβJuly; highly attractive to bees
fruits/seeds
Small, round, hard nutlet 4β6 mm diameter, gray-brown; finely ribbed; 1β2 per bract; not edible
Active Compounds
Traditional Uses
- European folk medicine used linden flower tea for colds, flu, and fever since at least the Middle Ages; referenced in Hildegard von Bingen's writings (12th c.)
- French tisane de tilleul remains a bedtime relaxant and sleep aid in widespread popular use
- German Commission E-approved for use in cold and cough remedies
- Traditional use in Slavic folk medicine for respiratory infections, bronchitis, and catarrh
- Inner bark used in European herbal tradition to treat epilepsy, vertigo, and liver diseases
- Linden charcoal used in French folk medicine for digestive complaints, gas, and diarrhea
- Topical poultice of fresh flowers used for skin inflammation, headaches, and rheumatic joints
- Flowers used in traditional Spanish and Italian medicine as a diaphoretic for breaking fevers
Modern Applications
- Anxiolytic: flavonoids and essential oil constituents show GABA-A receptor modulation in animal studies; clinical use supported by traditional evidence
- Sleep improvement: sedative effects documented in animal pharmacological studies; widely recommended by European phytotherapists
- Antispasmodic: smooth muscle relaxation reduces coughing and GI cramping in in vitro studies
- Diaphoretic: promotes perspiration to support fever resolution; pharmacologically plausible via prostaglandin modulation
- Antioxidant: tiliroside (kaempferol glucoside) shows potent antioxidant activity in DPPH and FRAP assays
- Anti-inflammatory: flavonoid fraction inhibits COX-1, COX-2, and 5-LOX in cell-based assays
- Antihypertensive: saponins and flavonoids show mild ACE-inhibitory activity in vitro
- Antimicrobial: essential oil components active against respiratory pathogens in vitro
β οΈ Safety Information
Contraindications
- Heart disease: traditional sources caution that large doses of old or poor-quality linden flowers may cause cardiac toxicity; avoid use >4 g/day with existing cardiac conditions
- Pregnancy: insufficient safety data for therapeutic use beyond food amounts
- Allergy to Tilia species or related Malvaceae family members
- Sedative medication use: additive CNS depression risk
Side Effects
- Excessive sweating (intended diaphoretic effect) may cause mild dehydration
- Sedation and drowsiness; impairs driving ability with high doses
- Rare allergic reactions (pollen allergy cross-reactivity): urticaria and contact dermatitis
- Gastrointestinal discomfort with very large doses
- Cardiac effects: rare reports of arrhythmia with excessive consumption (>10 cups/day) using old stored flowers
Drug Interactions
- CNS depressants (benzodiazepines, barbiturates, antihistamines): additive sedation and respiratory depression risk
- Antihypertensive medications: mild additive BP lowering effect
- Diuretics: additive fluid loss; monitor electrolytes
- Lithium: diuretic effect may raise serum lithium levels to toxic range
Parts Used
- Dried flowers with bracts (primary)
- Bark (inner bark, traditional)
- Leaves
- Charcoal from wood (traditional)
Preparation Methods
Flower tea (infusion): 2β4 g dried flowers in 250 ml boiling water, steep 10 minutes; 2β4 cups/day for anxiety or sleep
Cold infusion: 4 g flowers steeped in 200 ml cold water for 8 hours for maximum mucilage extraction
Tincture (1:5 in 45% ethanol): 3β5 ml three times daily
Standardized extract capsules: 300β600 mg/day
Flower honey (linden/basswood honey): 1β2 teaspoons in warm water as a traditional cold remedy
Steam inhalation: 2 tablespoons dried flowers in 1 L near-boiling water; inhale steam for respiratory complaints
Related Plants
Cacao
Theobroma cacao
Hibiscus
Hibiscus sabdariffa
Marshmallow
Althaea officinalis
Hops
Humulus lupulus
Horsetail
Equisetum arvense
Oat Straw
Avena sativa