Hawthorn: Research Notes

by | Oct 6, 2021 | agroforestry, cultivation, forest garden, harvest, medicinal, research, trees | 0 comments

Hawthorn (Crataegus monogyna) 

A small European tree, with fragrant flowers, leaves and red berries all providing benefits to the circulation.

Medicinal effects

The hawthorn is in the rose (Rosaceae) family. Medicinal actions are antioxidant, cardiotonic, vasodilatory, diuretic, astringent, antiinflammatory, hypotensive and antibacterial. Hawthorn has a history of use, confirmed safety, and clinical evidence to support its cardiovascular benefits, and has been shown to lower blood pressure in a number of studies (Blumental and Foster, 2000). Hawthorn preparations contain bioflavonoids which are anti-oxidant and help to prevent degeneration of blood vessels, they relax and dilate the arteries so increasing blood flow to the heart muscle. However, the benefits of this herb are felt only after prolonged use, at least 4–6 weeks (Tassell et al., 2010). Other benefits of this plant include relief of anxiety in a preparation with magnesium, hawthorn (Crataegus oxyacantha) and Californian poppy (Eschscholzia californica) taken twice daily for three months – patients showed a significant decrease in anxiety measured by self-report and the Hamilton Anxiety Scale (Hanus et al., 2004).

Growing

This is a thorny large shrub or small tree which is very hardy. Toothed leaves with 3 to 5 acute lobes are born on thorny branches. Pinkish-white flowers are produced early from May to June with the fruits ripening from September to November. Hawthorn is native to the northern wooded zones of Europe and will grow in light woodland or on a woodland sunny edge, but not in heavy shade. Hawthorn suits most soils, and prefers moist soil although it tolerates drought, maritime exposure and atmospheric pollution. Hawthorn can be repeatedly pruned and will form an impenetrable bush or hedge. Pollarding is not recommended as it may give rise to many weak growths. Seedlings take from 5-8 years before they start to bear fruit. A study of different methods of hedgerow management, predominantly hawthorn, found that the unmanaged areas were substantially more productive of berries, producing around 150 g (dry weight) per 2.5 m2 surface area of hedgerow (Sparks and Martin, 1999).

 

young alder plant

Harvesting

Flowers, leaves and fruits (berries) are all used. Flowers and leaves can be harvested in May, they may have a fishy smell (trimethylamine to attract insects) which disappears on drying. Berries are gathered in September/October when red and ripe and can be dried. Take extra care, wear thick gloves, to avoid the sharp thorns when harvesting.

Traditional use

Hawthorn has a considerable history of magical association and folklore. It was particularly associated with May Day festivities, and is also frequent in place names and boundary charters. Although used for decoration outside, there was a belief that it should not be brought into the house for fear of illness and death.

Ways to use

Dried flowers and leaves up to 6 g per day can be steeped as tea for 10-15 min

Dried berries, 2 g per day in decoction for a sore throat

Hawthorn berry tincture 1:5, 3.5 to 17.5 ml per day  

Fluid extract 1:1, up to 2 ml per day

A liqueur can be made with hawthorn berries steeped in brandy or other spirits

IMPORTANT NOTE

Hawthorn preparations are well-tolerated with little evidence for anything other than infrequent mild adverse effects of headache, nausea and palpitations. However, hawthorn preparations may enhance the actions of cardiac medications, anti-hypertensives and lipid-lowering medications, so medical advice should be sought if taking these. Seeds in the hawthorn fruits (like apple seeds) should not be eaten to excess as they can produce cyanide toxicity.

Other plants with similar effects

There are around 280 species of hawthorns in the genus Crataegus, and all are likely to have some medicinal effect. In the USA, C. monogyna is an introduced species and can be invasive, so other native species should be used such as C. douglasii. For further details on hawthorn and other medicinal species see The Medicinal Forest Garden Handbook (2020).

References 

Blumenthal, Mark, and Steven Foster. Herbal Medicine: Expanded Commission E Monographs: Herb monographs, based on those created by a special expert committee of the German Federal Institute for Drugs and Medical Devices.  Austin, Texas.: American Botanical Council, 2000.

Hanus, M., Lafon, J. and Mathieu, M. (2004) Double-blind, randomised, placebo-controlled study to evaluate the efficacy and safety of a fixed combination containing two plant extracts (Crataegus oxyacantha and Eschscholtzia californica) and magnesium in mild-to-moderate anxiety disorders. Curr Med Res Opin 20(1): 63-71.

Sparks, T. H. and Martin, T. (1999) Yields of hawthorn Crataegus monogyna berries under different hedgerow management. Agriculture, Ecosystems & Environment 72(2): 107-110.

Tassell MC, Kingston R, Gilroy D, Lehane M, Furey A. (2010) Hawthorn (Crataegus spp.) in the treatment of cardiovascular disease. Pharmacognosy Reviews 4(7): 32-41.