Tilia cordata, Small-leaved lime
A handsome medium to large tree with edible leaves and honey-scented flowers providing gentle sedative action and circulatory support.
scientific name Tilia cordata Mill.
family Malvaceae
alternate names Linden
parts used Flowers and leaves
Pollarded lime trees
Description
The small-leaved lime is a medium to large deciduous tree growing to 30m by 12m at a fast rate. Heart-shaped green leaves have toothed margins. It flowers in June-July and the yellowish-green fragrant flowers are borne in clusters. The flowers are hermaphrodite and pollinated by bees.
Habitat
The small-leaved lime is native throughout Europe.
Related plants
Flowers are also obtained from the large-leaved lime (T. platyphyllos). Lime trees hybridise freely and the common lime (Tilia × europea) is a hybrid of T. cordata and T. platyphyllos suitable for poorer soils. Tilia × europea is vigorous and readily produces suckers at the base. In the US, basswood (T. americana) can be harvested for flowers and leaves.
Cultivation and harvest
Cultivation
Lime is hardy to USDA zone 3 (UK zone 3). The small-leaved lime will grow in a range of soils though it prefers moist well-drained soil that is somewhat alkaline. It can grow in semi-shade and tolerates strong winds. This tree produces heavy shade. Lime can be readily coppiced or pollarded. Traditional pleaching involves pruning lime trees alongside each other to form a raised hedge. Trees begin flowering from 15-20 years of age.
Pests and diseases
The leaves can be infested with aphids which produce a sticky honey dew. Resistant to honey fungus.
Propagation
Fresh seed should be sown immediately in a cold frame before the seed coat hardens. It may germinate in the following spring though it could take 18 months. Stored seed is stratified for five months at high temperatures (10oC (50oF) at night, up to 30oC (86oF) by day) followed by five months’ cold stratification in a refrigerator. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for their first winter. Plant them out into their permanent positions in late spring or early summer, after the last frosts. Layering in spring, just before the leaves unfurl, takes 1-3 years. Suckers, when formed, can be removed with as much root as possible during the dormant season and replanted immediately.
Harvesting
Collect the clusters of lime flowers when some of them are open (recognisable with their stamens), while others may still be closed, including the small leaves or bracts on the flowers. Hang in bunches to dry. Lime flowers are said to develop narcotic properties as they age and so they should only be harvested when young. Take care when harvesting as the nectar-rich flowers are attractive to bees.
Therapeutic use
Traditional
Lime flowers have traditionally been used widely in Europe,1 especially as a diaphoretic to promote perspiration. They have been used for a soothing tea and as a mild sedative to treat headaches and in insomnia and epilepsy. The leaves are mucilaginous and were used in poultices.
Medicinal actions and uses
Lime flowers are antispasmodic, diaphoretic, diuretic, sedative and vasodilatory. The leaves are demulcent and anti-oxidant. Lime flowers are a popular domestic remedy for colds and catarrhal ailments. Lime flower tea is also used in the treatment of hypertension, hardening of the arteries, indigestion and nervous complaints.2
Lime flowers
Clinical applications and research
Little significant clinical research has been carried out and lime flower use is based on tradition and knowledge of the constituents. The sedative activity of the flowers is probably due to flavonoid derivatives of quercetin and kaempherol.3 The anti-inflammatory effects of procyanidins in the flowers have been identified to support the traditional use of lime flowers in treating colds and sore throats.4 Both the flowers and leaves have been found to be rich in anti-oxidant polyphenols5 supporting further use in neurological degeneration related to oxidative stress such as Parkinson’s disease and Alzheimer’s disease.
Sample preparations and dosage
Herbal tea daily dose of 3-6g dried flowers, or use around five fresh blossoms for a cup of tea and infuse for five minutes. Tincture of limeflowers dose of 1-3ml three times daily.
Constituents and commerce
Key constituents
Lime flowers contain 1% flavonoids (particularly heterosides with quercetin and with kaempferol) alongside polysaccharides, condensed tannins, phenylcarboxylic acids, amino acids, saponins, volatile oils and proanthocyanidins. Farnesol, a sesquiterpene, is considered to be a significant constituent of the flowers, having antispasmodic properties.
Commerce
The European Medicines Agency acknowledges well- established use of lime flowers (T. cordata and T. platyphyllus) for relief of symptoms of the common cold and mental stress. Lime flowers are widely available in teabags or sold whole loose for infusions throughout Europe and the US. Harvesting takes place in Bulgaria, Romania, Turkey, and other parts of Eastern Europe as well as China.
Safety
Lime flower preparations are generally regarded as safe. However, if the flowers are harvested when too old they may produce symptoms of intoxication.
Other uses
Wildlife plant especially for bees. Edible buds and leaves. Hedge or shelterbelt.
1 Pranskuniene Z, Dauliute R, Pranskunas A, et al. (2018) Ethnopharmaceutical knowledge in Samogitia region of Lithuania: Where old traditions overlap with modern medicine. J Ethnobiol Ethnomed 14: 70.
2 Barker (2001) section 186.
3 Negri G, Santi D and Tabach R. (2013) Flavonol glycosides found in hydroethanolic extracts from Tilia cordata, a species utilized as anxiolytics. Revista Brasileira de Plantas Medicinais 15: 217-224.
4 Czerwińska ME, Dudek MK, Pawłowska KA, et al. (2018) The influence of procyanidins isolated from small-leaved lime flowers (Tilia cordata Mill.) on human neutrophils. Fitoterapia 127: 115-122.
5 Wissam Z, Nour AA, Bushra J, et al. (2017) Extracting and studying the anti-oxidant capacity of polyphenols in dry linden leaves (Tilia cordata). J Pharmacogn Phytochem 6: 258-262; Cárdenas-Rodríguez N, González-Trujano ME, Aguirre-Hernández E, et al. (2014) Anticonvulsant and anti-oxidant effects of Tilia americana var. mexicana and flavonoids constituents in the pentylenetetrazole-induced seizures. Oxid Med Cell Longev 2014: 329172.