Plant remedies: Back to our roots

Right now the roads near us are lined with elder in bloom, the flowers balanced precariously like plates of whipped cream and the air thick with their heady scent. I've made a sorbet with the flowers and have been liberally dosing my husband with last autumn's elderberry liqueur to help relieve a cold. Apparently, as well as being good for coughs, the berries are packed full of vitamins A and C and anthocyanin, an antioxidant.

This is about the limit of my hedgerow knowledge, for, like most of us, I have little idea about what to do with British plants. "We've spent so long popping down to the chemist that we're in danger of losing traditional herbal recipes," says Rosie Atkins, the curator at Chelsea Physic Garden.

To counteract this loss of knowledge, Kew Gardens is working with the Natural History Museum, Chelsea Physic Garden, the Eden Project and British herbalists on an Ethnomedica Project to collect people's herbal remedies; so far they've found 3,000.

Professor Monique Simmonds, who is head of the Ethnomedica Project at Kew, says: "It's the range of uses that are interesting, as plants are used differently around the country. Most of us know dock leaves offset the sting from nettles, but in France, this isn't a common use. We have very quirky, UK-based remedies."

Rhiannon Evans, a medical herbalist who chairs the Ethnomedica Remembered Remedies Group, says that the way plants were used historically may not reflect how a qualified herbalist would use them today. "I would recommend my children rub dock leaves on a nettle sting because you can use dock found growing by the wayside but, in professional practice, you need to use specific species. For instance, the root of yellow dock can, in some cases, be used as a laxative."

Roy Vickery, senior curator in the department of Botany at the Natural History Museum, donated his own database on folk remedies to Kew. He says that one of the most useful plants is the elder. In the Forties he received a letter from a man who lived in the Forest of Dean, who wrote that local people would take an infusion of elder flowers if anything was wrong with them. Only when that failed to work would they see a doctor.

What is unusual about the elder is that every part - even the fungus that grows on the trunk - has been used in traditional remedies.

There is a certain anthropological satisfaction in categorising our country's herbal remedies, but do any of them work? Simmonds says that early investigation into dock shows that not only does it have an antibacterial effect, it could well combat nettle stings because it contains compounds that have an antihistamine-type action. Simmonds and her team, in collaboration with the pharmacology group at King's College, London, are testing a number of our native plants to see exactly what compounds they contain and what they could be used for.

Many of the plants, like dock and ground elder, are classed as weeds and, in spite of the irritation they cause gardeners, she thinks this is what makes them so exciting scientifically. "If a plant can survive in difficult circumstances, it must have a strong chemical profile - it must be able to replicate itself quickly and protect itself from predators and fungi, bacteria and insects."

Simmonds has run into a problem she hadn't anticipated, though. One of the plants she has been examining is the figwort, a shade- and damp-loving plant with innocuous, unpleasant-smelling flowers. In Ireland it was regarded as the "queen of herbs" and was used to heal wounds. Simmonds thought it could be useful for diabetics, who can often suffer from leg ulcers. "We identified some of the main ingredients but when we extracted these compounds, we discovered they were totally inactive," says Simmonds.

Simmonds went back to the herbalist who had given her the information, and asked for a sample of the material she was using. She discovered that the compounds she was interested in, the iridoids and flavonoids, had been destroyed when the extracts were made. "We don't always look very carefully at how people prepare their herbal medicines. In the 17th century, doctors wouldn't have written this down - it was their way of earning money."

By looking at how figwort is used today - fresh, as a poultice - the team were able to isolate the active ingredients. Simmonds is now hoping to begin clinical trials.

Other plants that are being examined are raspberry leaf - an infusion of the leaves could help alleviate TB; bugle, which could reduce blood pressure; violet, which is thought to be an anti-inflammatory, and lavender, which may contain antibacterial agents.

Throughout history, sage has been connected with wisdom, hence its name. A group at Newcastle University, has found that sage oil can improve memory. In a trial they've also discovered that it improves the attention span of Alzheimer's patients. Now if I could find a recipe for sage and nettle beer, I might be able to get my husband to eat herbs, too.

Traditional remedies are collected at the Eden Project, Cornwall, the Chelsea Physic Garden, London, and at the Kew Heritage Festival, which runs until 24 September, or can be sent to Monique Simmonds at m.simmonds@kew.org

Cures from Mother Nature

The 10 most popular plants and their remedies, collated by Kew's Ethnomedica Project: www.rbg kew.org.uk/ethnomedica/

Dock Rubbed on nettle stings.

Onion Cut into slices, covered with brown sugar and left until the juices run out. This syrup was used to alleviate coughs.

Garlic The leaves and bulbs were eaten as a general tonic.

Nettle The tips of the leaves were infused in boiling water. The resulting tea was drunk as a tonic and to purify the blood.

Feverfew A garland of these daisy-like flowers was worn around the head as a migraine remedy.

Elder The flowers can be made into a tea as a cold or flu remedy.

Comprey Traditionally the fresh leaves or a poultice were used to heal broken bones or sprains, but its use is restricted today.

Lavender The dried flowers were put into a sachet and placed under the pillow for insomnia.

Cabbage Fresh leaves placed against the breast were thought to help alleviate mild cases of mastitis.

Dandelion A tea made from the leaves was used as a diuretic and for arthritis.