
Dear Readers, you might remember that recently I went to Wicken Fen, and fell in love with the Marsh Thistles (Cirsium palustre) that were growing there. This is a tall, multi-flowered thistle, and every plant that I saw was covered in bees, moths, hoverflies or other pollinators. And no wonder! In a survey in 2014, Marsh Thistle was found to have the highest per hectare nectar production of any plant: together with White Clover and Heather, it produces nearly 50 percent of all the nectar in the country. Pretty impressive for a plant that has such specialised conditions, preferring damp but not completely sodden ground, such as that found in meadows and fens.

Marsh Thistle is found throughout temperate Europe and into central Asia (and also in many parts of North America, where it has become invasive) – it was probably brought accidentally with human settlers from the Holocene onwards. Unlike other thistles, it doesn’t spread by underground rhizomes so you are more likely to see individual plants. However, as a single plant can produce up to 70,000 seeds, and as these seeds can survive for at least five years in the soil, I’m surprised that we’re not up to our necks in Marsh Thistles. It’s thought that the UK Marsh Thistle might be spinier than its European conspecifics, which might also put off a fussy grazing animal. But also, the leaves are munched upon by the caterpillars of several butterflies and moths, including those of the Painted Lady (who migrates all the way from the Atlas Mountains to get here), the Red Sword-Grass moth and the Broom Moth. The seeds are also often favoured by small birds such as finches, though the ones in my garden much prefer the sunflower seeds in the feeders, which I assume are easier to get at.

Red Sword-Grass Caterpillar (Xylena vetusta) (Photo By Tarmo Lampinen – Copyrighted free use, https://commons.wikimedia.org/w/index.php?curid=27055228)

Broom Moth caterpillar (Ceramica pisi) Photo By Ivar Leidus – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=116228633

Painted Lady (Vanessa cardui) Photo By Jean-Pol GRANDMONT – Self-photographed, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=27747981
The young leaves are said to be edible, and the stems can be eaten raw or cooked (allegedly). I suspect there are easier ways of getting one’s dinner. Apparently the ‘fluff’ from the seeds can be used as tinder. The plant was thought to be useful for the treatment of varicose veins – ‘kirsos‘ in Greek, from which we get the generic name ‘Cirsium‘. Who knew?
Interestingly, Culpeper the herbalist mentions that Marsh Thistle was ‘frequent in the Isle of Ely’, not far from Wicken Fen.

And here’s a poem, by the ever-observant John Clare. I love that he describes the thistle as ‘the very wasp of flowers’, and you’d have to be very determined indeed to pick a Marsh Thisle, for sure.
The Marsh Thistle (John Clare (1793-1864)
The nodding oxeye bends before the wind,
The woodbine quakes lest boys their flowers should find,
And prickly dogrose spite of its array
Can’t dare the blossom-seeking hand away,
While thistles wear their heavy knobs of bloom
Proud as a warhorse wears its haughty plume,
And by the roadside danger’s self defy;
On commons where pined sheep and oxen lie
In ruddy pomp and ever thronging mood
It stands and spreads like danger in a wood,
And in the village street where meanest weeds
Can’t stand untouched to fill their husks with seeds,
The haughty thistle oer all danger towers,
In every place the very wasp of flowers.






























