Digitalis Purpurea and a Shropshire Hedgerow

I have always loved foxgloves (Digitalis purpurea). I love to watch the bees going in and out of the flowers collecting the pollen and as a child, I liked to make finger puppets with the flowers. 

All parts of the plant are extremely poisonous and ingestion can be fatal, but important cardiac glycosides (digitoxin, digitalin, digitonin, digitalosmin, gitoxin and gitalonin) can be obtained from the leaves and the plant has a remarkable history.

In 1785 William Withering, a Shropshire doctor and botanist investigated the plants properties after learning that a local folk herbalist, said to have been a Mrs Hutton had successfully used it to treat dropsy (oedema), a condition associated with heart failure and characterized by the accumulation of fluid in soft tissues. He considered the plant to contain a diuretic but we now know that it is the action of the glycosides on the heart that alleviate the oedoema, by improving the efficiency of the heart and slowing down the heart rate. Since that time countless patients have been successfully treated with minute doses of digitalis or its active constituents. I came across a short poem from 1818 which I liked, thought to have been written by a Miss Sarah Hoare whose father had been treated with digitalis.

The Foxglove's leaves, with caution given,

Another proof of favouring Heav'n,
Will happily display;
The rapid pulse it can abate;
The hectic pulse can moderate;
And blest by Him whose will is fate,
May give a lengthened day.

By 1869, a French pharmacist, Claude Adolphe Nativelle, had isolated a much-purified material he called “digitalin” from foxglove. Six years later, German chemist Oswald Schmiedeberg, whom many consider the father of pharmacology isolated the first pure glycoside in crystal form from foxgloves, which he called “digitoxin”. A brand of digitoxin called 'Nativelle Digitaline' was marketed in the UK at least as late as the mid 1980s.
Nowadays, digoxin is the cardiac glycoside of choice medically. It is obtained from a related plant Digitalis lanata which grows in Eastern Europe (although during the Second World War D. purpurea seeds were collected from the wild and grown to produce large quantities of leaves for medicinal use and at least as late as 1968 digitalis tablets prepared from the leaf were still in the British National Formulary).
With the possible exception of the opium poppy, digitalis species are probably the most important medicinal herbs known.

Nice marking on the inside of the foxglove flower.

A biennial and a popular cottage garden plant there are also pale and white varieties.