Marsh Sowthistle, Sonchus palustris

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Marsh Sowthistle, Sonchus palustris, by the River Yare.

Marsh Sowthistle, Sonchus palustris, by the River Yare.

If you visit the Norfolk Broads or the coastal wetlands of Suffolk you may encounter a tall, stately plant with yellow flowers growing in the marshes and on some of the riverbanks. This is Marsh Sowthistle, Sonchus palustris.

Marsh Sowthistle (also known as Fen Sowthistle) is a perennial plant. It has long, lance-shaped leaves with two backward-pointing lobes at the base. In late spring the plant produces tall stems which can reach 2.5 or even three metres (8 – 9.5 feet) tall, each one bearing many-branched bunches of yellow flowers. Flowers are produced from May to September but usually peak in late July and early August. They are followed by seeds with fluffy white parachutes, which are dispersed by the wind.

Sonchus palustris flower

Sonchus palustris flower and buds.

Sonchus palustris flower head

Sonchus palustris flowerhead with some seeds forming.

Sonchus palustris is a member of the Daisy family, Asteraceae (formerly known as the Compositae) and each flower head is a composite structure consisting of lots of individual small flowers (florets). Yellow-flowered Asteraceae can be difficult to identify but Sowthistles are some of the easiest and Marsh Sowthistle is pretty impossible to confuse with any of its relatives because of its sheer size (note 1).

Sonchus palustris has a restricted range in the British Isles. It is absent from Scotland and Ireland and the native populations are in the Norfolk Broads and East Suffolk (where the plant is increasing in number) and the Thames valley and North Kent (where urban development has caused a decline). A population of plants found in Hampshire in 1959 is also thought to be native.

The original populations of Marsh Sowthistle in Cambridgeshire became extinct through drainage long before 1930 but the plant was reintroduced to Woodwalton Fen in Huntingdonshire and has now spread out along the River Nene and drainage channels in the Fens. Marsh Sowthistles by the Humber in Yorkshire were probably introduced with willows from East Anglia. There is also a small colony of Marsh Sowthistle in Bedfordshire and a single site in Wales.

Outside the British Isles, Sonchus palustris is a native of much of Europe, east into Turkmenistan, Uzbekistan and western Russia, reaching as far south as Iran, Turkey and Spain. It is absent from Portugal and Finland and became extinct in Italy. Sonchus palustris has been introduced into Ontario in Canada, where it occurs at two widely separate sites (note 2).

In Norfolk, two of the best places to see Marsh Sowthistle are Strumpshaw Fen RSPB Reserve and the Ted Ellis Reserve at Wheatfen, where walking along a path lined with magnificent Marsh Sowthistle plants is one of the highlights of any visit in July and August.

Marsh Sowthistles at Wheatfen

Marsh Sowthistles, Great Willowherb and Common Reed at Wheatfen. 8th August 2022.

Marsh Sowthistle featured at a key moment in the lives of Ted and Phyllis Ellis, who lived at Wheatfen and  studied plants, fungi and wildlife throughout their lives. Phyllis studied Botany as part of her teaching diploma and in 1934 she was observing Marsh Sowthistles on St. Olave’s Marsh (by the River Waveney). Ted was also on site and noticed her interest in the plants. He approached her, thinking that she might be up to no good, possibly about to dig up the plants. This is said to be the first time they spoke; they married four years later (note 3).

Marsh Sowthistles were much rarer in Norfolk in the 1930s. In 1957, in one of his nature columns, Ted Ellis attributed the increase in plants to the dredging of waterways, where the dredged spoil on riverbanks provided an ideal place for Marsh Sowthistle seeds to germinate (note 3).

Sowthistles have hollow stems containing a white latex that bleeds when they are cut or broken. Their English name comes from the practice of feeding sowthistles to lactating sows in the belief they would produce more milk. Sonchus means “hollow” and palustris refers to the damp ground where Marsh Sowthistle grows.

In general, sowthistles are edible and the young leaves can be eaten raw or cooked and contain good levels of vitamins A, B, C and K, but old leaves are bitter and tough. There are some sowthistle recipes on the Eatweeds website.

Sowthistles also had various medicinal uses: the latex was used as a cure for warts and parts of the plants were used to hasten childbirth, treat skin and eye problems and freshen foul breath. The Plants For A Future website has specific entries for the food and medicinal uses of Prickly Sowthistle (Sonchus asper) and Smooth Sowthistle (Sonchus oleraceus). As always there is the caveat: “Always seek advice from a professional before using a plant medicinally.”

But it’s best to stick to Prickly Sowthistle (Sonchus asper) and Smooth Sowthistle (Sonchus oleraceus) if you’d like to add sowthistles to your diet. Marsh Sowthistles should be admired rather than eaten.

Notes

Note 1 – Mike Crewe’s Flora of East Anglia website gives a useful comparison of the yellow-flowered Asteraceae that grow in East Anglia.

Three other species of Sonchus (Sowthistles) occur in the British Isles and the Botany In Scotland blog has a post on how to tell them apart. Prickly Sowthistle (Sonchus asper) and Smooth Sowthistle (Sonchus oleraceus) are both annual plants, found on disturbed ground such as in gardens and on roadsides and the edges of arable fields. Perennial Sowthistle (Sonchus arvensis) also grows on waste ground but also on river banks and ditches at the coast. All three grow to 1.5 metres tall, much shorter than Marsh Sowthistle.

My favourite of the three is Perennial Sowthistle, which I tend to call Corn Sowthistle, the name I learnt from my first flower book, Keble Martin’s Concise British Flora in Colour. (Keble Martin used “Fen Sowthistle” as the English name for Marsh Sowthistle but it wasn’t a plant I’d seen.)

For completeness, the “New Flora of the British Isles“ by Clive Stace (Fourth Edition, 2019) also lists a hybrid between S. oleraceus and S. asper which has occurred very rarely in England but “most records [are] doubtful or erroneous” and Slender Sowthistle (Sonchus tenerrimus), a rare casual from Southern Europe.

There are 106 species of Sonchus worldwide.

“Sowthistle” is sometimes spelt “Sow-thistle”.

Note 2 – The Plantnet website also shows some occurences in the United States, eastern Africa and eastern Australia, but the Kew Plants Online website makes no mention of these.

See the INPN website for the distribution of Sonchus palustris in France.

Note 3 – From the Ted Ellis Trust booklet “Wildflowers of a Broadland Reserve Wheatfen. Part 1: Species of the fen and reedbeds”, written by Will Fitch, the current warden of Wheatfen.

Phyllis Ellis died in 2004 but I was fortunate to meet her in the late 1990s when I took part in a conservation task at Wheatfen. She was very hospitable and invited us in to have tea and cake in her living room.

Bog Pimpernel, Lysimachia tenella

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Bog Pimpernel, Lysimachia tenella

Bog Pimpernel, Lysimachia tenella. Buxton Heath, 2nd July 2023.

Bog Pimpernel, Lysimachia tenella, is a creeping, evergreen perennial that grows in wet open places such as fens, bogs and mires. Its creeping red-tinged stems bear pairs of leaves and then delicate pink flowers appear on short stalks in summer, usually from June to August. Bog Pimpernel’s flowers open fully on sunny days and have  five petals, each with 7 or 8 darker pink stripes. It’s a lovely colour combination.

I learnt Bog Pimpernel’s scientific name as Anagallis tenella, but since then it has been moved to the genus Lysimachia. Bog Pimpernel now belongs with loosestrifes (such as Yellow Loosestrife, L. vulgaris, which I wrote about in August 2020) and several other pimpernels, including Yellow Pimpernel (L. nemorum) and the elusive, sought after Scarlet Pimpernel (L. arvensis, note 1). The genus Lysimachia is part of the Primrose family, the Primulaceae.

Lysimachia tenella is a native British plant and grows in several places in Norfolk, such as Holt Lowes and Buxton Heath. When I visited Buxton Heath earlier this month there was a lot of Bog Pimpernel in flower in the valley mire and smaller patches in damp areas at the top of the Heath. Thirty years ago there was just one area where the plant grew, a square in the valley mire where the top of the turf had been removed, creating a tiny damp depression (note 2).

The recent success of Lysimachia tenella at Buxton Heath is very encouraging but is sadly not typical of the plant’s fortunes. Bog Pimpernel is commoner in the west of the British Isles, including Ireland. In general the south and east of England are not the best places to look for Bog Pimpernel and in recent hot and dry summers Bog Pimpernel’s shallow root system and need for moisture have caused the plant a lot of stress. Historically, the plant has been lost from many places through drainage of wetlands, an excess of nutrients and agricultural “improvement”.

Outside the British Isles Lysimachia tenella is a native of Europe from Greece to Ireland and the Faeroe Islands and North Africa (Algeria, Morocco, and Tunisia). It has been introduced into southern Brazil. In Germany the plant has suffered declines of 99.8% since 1960 (note 3).

Bog Pimpernel, Lysimachia tenella

Bog Pimpernel, Lysimachia tenella. Leaves and red-tinged stems at Holt Lowes, August 2021.

I have only seen Bog Pimpernel growing in the wild but the Royal Horticultural Society website lists it as a plant that can be grown in a sunny spot with moist but well drained soil in a garden. If you have the right conditions in your garden it is certainly hardy (H4, down to between -5 and -10 Celsius) and there is even a garden cultivar called ‘Studland’. The Pond Informer website suggests growing Bog Pimpernel around the shallow edges of a pond. The First Nature website says the plants are wonderful additions to any bog garden or to the waterlogged margin of a small pond. There are several stockists in the British Isles if you’d like to grow it – please don’t dig it up from the wild.

Bog Pimpernel isn’t considered to be edible and isn’t listed on the Plants For A Future website. It is just something to admire, and surely that is enough (note 4).

Bog Pimpernel, Lysimachia tenella

A delicate delight – Bog Pimpernel, Lysimachia tenella. Buxton Heath, 2nd July 2023.

The First Nature website still uses the older name, Anagallis tenella, and tells us that tenella means “delicate or tender” and Anagallis  comes from Greek and means “to delight again”. How very appropriate for this lovely flower.

Notes

Note 1 – As in the novel “The Scarlet Pimpernel” by Baroness Orczy, written in 1905:

“They seek him here, they seek him there
Those Frenchies seek him everywhere
Is he in heaven or is he in hell?
That demned elusive Pimpernel”.

Note 2 – For just over a year (June 1993 until July 1994) Vanna and I spent most of our Saturdays on Buxton Heath, volunteering with the Buxton Heath Wildlife Group. In those days the group was run by Colin Penny, who no longer runs the group but whose quirky but sadly incomplete website still exists. The Norfolk Biodiversity Partnership website gives more up to date details for the group.

Back in the 1990s the management of Buxton Heath required lots of hard but enjoyable human toil.
Today a lot of the work is done by horses and cattle. This has led to many benefits to biodiversity, not just for Bog Pimpernel. See my May 2019 blog post about Nail Fungus for another example.

Note 3 – Eichenberg et. al. (2020), “Widespread decline in Central European plant diversity across six decades“. Global Change Biology, Vol. 27, pages 1097-1110. The article is open access. (I wish more were.)

Note 4 – There are lots of lovely photos of Lysimachia tenella on the internet, including on the Wildflower Finder, British Wildflowers, UK Southwest, Wildflowers of Ireland and First Nature websites.

Giant Fennel, Ferula communis

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“From a huge mound of dark-green, finely-cut foliage rises the vast flower-stalk, thick as a broomstick, purple tinted, topped with yellow umbellifer flowers.” – Description of Giant Fennel, Ferula communis, on Beth Chatto’s Plants & Gardens website.

Giant Fennel, Ferula communis (with touring bikes)

Giant Fennel, Ferula communis (with touring bikes). Gorges de l’Ardèche, France, 21st June 2008.

Giant Fennel Abroad

I first noticed Giant Fennel, Ferula communis, in June 1987 in Corsica, growing in the Gorges de Tavignano near Corte (note 1). But my first photograph of the plant (shown above) is from many years later, from a fortnight’s cycle touring in southern France.

Giant Fennel is very impressive when in flower, when each plant has a stem two to three metres (6 – 10 feet) tall, topped with umbels of flowers in bright yellow ball-like clusters. These glow in sunshine and especially in low evening or morning light. Ferula communis is made even more dramatic by the dramatic, rocky surroundings in which it grows.

Giant Fennel, Ferula communis is a native of Mediterranean Europe, the Middle East and East Africa, as far south as Uganda, Kenya and Tanzania. It is much bigger and more dramatic than Common Fennel, Foeniculum vulgare, which is is used as a culinary herb and ornamental plant. Both plants have umbels of flowers and are members of the Apiaceae (Carrot family). You can compare pictures and descriptions of the two plants on the Flora of East Anglia website (note 2).

In its native range Giant Fennel grows on both rocky and grassy hill slopes and, in East Africa, on mountain tops, in open forest, wooded grassland (both dry and wet) and on pasture land.

Giant Fennel At Home

Giant Fennel needs well drained soil and plenty of sunshine, with some late winter and early spring rainfall during its main growth period.

Although Ferula communis is native to hot, sunny climes it can grow in parts of the British Isles.  It is sometimes grown in gardens and naturalises from time to time (note 3). Giant Fennel is only hardy down to about minus 5 degrees Celsius, so a particularly cold winter could wipe out an established plant. However, human activity can do this too. Mike Crewe recounts on his Flora of East Anglia website that “a single plant beside the A11 north of Barton Mills was something of a celebrity for many years and even earned its own roadside nature reserve“, but was destroyed when the A11 was dualled.

I acquired a Giant Fennel plant several years ago and it grows in a sheltered, south facing raised bed in our front garden (note 4).

Ferula communis is a perennial plant which develops a sturdy tap root and can take several years to produce flowers. Younger plants produce feathery leaves in late winter and early spring, which yellow and die back later in the spring, leaving no trace of the plant.

This happened for several years with our plant, but this March we noticed it was starting to produce a flowering shoot.

The flower shoot grew upwards rapidly and reached full height in early April.

Giant Fennel, 2nd April 2023.

In bud. Our Giant Fennel, 2nd April 2023.

The umbels developed quickly too and the flowers opened from mid April and were at their peak in late April and early May. (It can be later – some websites list flowering time as early summer or even July and August.)

Giant Fennel, 8th May 2023.

In full glory. Our Giant Fennel, 8th May 2023.

As I write this in early June the stems have developed their purple tint and the plant has set seed, though only on the largest umbels.

Giant Fennel, 5th June 2023.

Gone to seed. Our Giant Fennel, 5th June 2023.

Our plant leant forward as it grew, partly to reach more light and partly as it was dashed down by heavy rain in late April and early May. I had to tie it up with a piece of string; a large stake would probably have been more elegant.

I am not sure whether our Giant Fennel will flower again. Ferula communis is often thought to be monocarpic (plants flower once, set seed then die). However, “others beg to differ, including renowned plantsman Bob Brown of Cotswold Garden Flowers“. Apparently if the flowering stem is removed before it has had a chance to set seed, the plant will live to flower again. I plan to let the seed ripen on our plant and I will need to wait until late winter to see whether our plant is still alive.

I wonder whether last year’s heat and drought, followed by winter rain and a sunny February enticed our plant to flower.

Giant Fennel: toxic and edible chemotypes

Common Fennel, Foeniculum vulgare, is a useful edible plant (both as a flavouring herb and a vegetable).  But I would suggest treating Giant Fennel purely as an ornamental plant.

Sensible advice is that “though in the same family as culinary fennel (Foeniculum vulgare), Giant Fennel is considered toxic to ingest and should not be eaten“.

The Plants For A Future website says that the leaves of Ferula communis are edible and according to Wikipedia the young stems and inflorescences of Ferula communis were eaten in ancient Rome, and are still eaten in Morocco today. The Gozo In The House website says that unopened inflorescences can be steamed and served with added olive oil and vinegar.

So far, so good. But the problem is that there are two different chemotypes of Ferula communis and plants that look identical can contain different levels of secondary metabolites, making one plant toxic and the other harmless (note 5).

Other Uses

The resin contained in the roots of Giant Fennel has been used for medicinal purposes, to cure a variety of ailments. (See the Gozo In The House website for more details of medicinal uses.) The related plant Ferula assa-foetida, from southern Iran, gives us the smelly ingredient asafoetida, used in Indian cooking (note 6).

Giant Fennel stems were used to make rods and whips for disciplinary purposes. The Latin word ferire (to hit), and the Swedish färla (a disciplinary tool used in schools in the past) come from Ferula.

Hollow stalks of Giant Fennel were sometimes used as torches, as they contain a flammable pith that burns slowly and evenly without destroying the outer stalk. This is said to be how Prometheus, in Ancient Greek mythology, stole fire from the Olympian gods and to give to humanity (note 7).

We plan to dry most of our plant’s stem as an ornament but will cut a small section of the lower stem once it has dried, to use as a torch.

Grow Your Own Giant Fennel

Ferula communis seeds are available from several suppliers, such as Plant World Seeds and Special Plants Nursery. A glaucous variety of Ferula communis, ssp. glauca, is sometimes available from Beth Chatto’s Plants & Gardens as a potted plant.

Tawny Mining Bee, Andrena fulva, on Giant Fennel.

Female Tawny Mining Bee, Andrena fulva, on our Giant Fennel.

Insects like the flowers – beetles and bees in Crete and in southern France. In our garden it attracted a variety of bees and flies, though the weather was rather cold and windy this spring and I would expect more insect visitors in warmer weather.

I would certainly recommend growing Giant Fennel, if you have the patience to wait for it to flower and well drained soil and a sunny, sheltered spot in your garden. The reward is worth it, I think.

Notes

Note 1 – I know this because I made a note in pencil in the guide to Mediterranean flowers that I bought there.

Note 2 – There are also other species of Ferula in the Mediterranean area, such as Ferula tingitana (Giant Tangier Fennel), which I have seen growing on the rock of Gibraltar and Ferula melitensis (Maltese Giant Fennel), which is endemic to the island of Malta.

Note 3 – On page 858 of the “New Flora of the British Isles“ by Clive Stace (Fourth Edition, 2019) mentions naturalised colonies on roadside verges in West Suffolk since 1988, in Northamptonshire (1956 – 1988 and 1996) and South Essex since 2004.

Note 4 – I’m trying to remember where it came from. I thought I grew it from seed but I now think I bought the plant in a pot from somewhere.

Note 5 – See Zucca et. al., “Isolation and characterization of polyphenol oxidase from Sardinian poisonous and non-poisonous chemotypes of Ferula communis (L.)”. Phytochemistry Vol. 90, pp 16 – 24 (2013).

Note 6 – The Ancient Greeks and Romans used silphium as a seasoning in their cookery, and as a perfume, aphrodisiac, medicine and contraceptive. It probably came from a species of Ferula, or a closely related plant. Is that plant now extinct? Pliny thought so.

Note 7 – Prometheus suffered for this. His  punishment was to be tied in chains and for an eagle (Zeus’ animal familiar) to eat his liver. Every night his liver regenerated and the punishment resumed the next day.