Yellow flag just coming into bloom, Sunday 10th May 2026
Dear Readers, the yellow flag iris have certainly established themselves in the pond since I wrote my first Wednesday Weed back in 2020. It always amazes me how some plants are happy and some aren’t – the water mint has gone and so have the marsh marigolds that I was told were indestructible. Hah! Still, the damselflies love the iris leaves, and I love the buttery yellow flowers, so everyone is happy. And the boggy patch by the tennis courts in Cherry Tree Wood is getting more interesting by the year.
Let’s time-travel back to 2020.
Yellow iris (Iris pseudacorus)
Dear Readers, round by the tennis courts in Cherry Tree Wood there is a place which is damp and muddy almost all year round. Some say that this is actually where the Mutton Brook arises before it makes its way through Hampstead Garden Suburb and eventually into the Dollis Brook. Whatever the truth of it is, I have never seen such a fine batch of yellow irises (Iris pseudacorus) as are there this year. They are the colour of butter, and those strange flowers are decorated with faint landing pads to show the hoverflies and bees exactly where to go to pollinate them.
I have some of these plants in the garden too, and the flowers are fleeting, appearing in the morning and sometimes gone by late in the afternoon. Still, I am not complaining – this is only the second year that they have flowered, and they are better than last year, when I only had a single bloom. For all its delicate beauty, it can be a bit of a thug – it is counted as an invasive species along the whole west coast of North America, and in New England as well. You can see how a stand of this plant would soon squeeze out everything else.
In the UK, the plant has a host of vernacular names, including butter-and-eggs, ducks’ bills, queen of the meadow and soldiers-and-sailors. Regular readers will be delighted to hear that this is yet another plant that’s considered to be unlucky if you bring it into the house: Roy Vickery speculates that it’s because the plant grows in treacherous, boggy areas. However, in Guernsey it was used to strew the path in front of a bride as she made her way to church on her wedding day, so it’s not all bad. In Shetland, irises are known as ‘segs’, which comes from the Anglo-Saxon word for a sword, an obvious reference to the blade-shaped leaves. Biting a ‘seg’ meant that you would develop a speech impediment such as a stammer. Goodness knows what it all means, except that people do love a good story, and plants are so often vehicles for such things.
The roots of yellow iris can be used to make a dye: in the Western Isles the dye is said to be black, and sometimes used as ink, while in Shetland it’s blue-grey or dark green. The flowers can be used to produce a dye too, while the leaves made a green dye that was used to colour Harris tweed. In short there’s a veritable rainbow of potential colours in the various parts of this plant.
Medicinally, yellow iris was used as a cathartic – it contains chemicals which can cause dermatitis, and is said to be mildly toxic to cats and dogs. However, it’s been used for everything from toothache to cramp and, if ground into snuff, was said by one Dr Thornton to have ‘cured complaints of the head of long standing in a marvellous way’.
Furthermore, it is said to have cured a pig following a bite from a mad dog. With all these medicinal uses, it’s no wonder that the Roman word for the plant was consecratix, because it was used for purification ceremonies.
It’s often thought that the yellow iris was the origin of the fleur-de-lys, symbol of French kings and boy scouts. The Frankish king, Clovis, was said to have replaced the three toads on his flag with three fleur-de-lys as a symbol of Christian purity. Later legends have the name ‘fleur-de-lys’ being a corruption of the phrase ‘flower of Louis’, for King Louis IX. However, it might also refer to the River Leie in Flanders, where yellow irises grew in great profusion. For me it will always be a symbol of the scout movement. How I remember trying to join the Cub Scouts as a child because the Brownies seemed a bit wet. Oh, the shame of being rejected at such a young age!
King Clovis of the Franks receiving the fleur-de-lys (British Library, public domain)
Although Claude Monet was famous for his paintings of waterlilies at his garden in Giverney, he was not averse to yellow irises either: I love how, in the painting below, the citrus-lemon colour of the flowers is offset by the blue-green of the leaves. Although the painting is not photo-realistic, it gives a real sense of the coolness of the plant – whenever I look at them, I seem to smell the freshness of water and see the faintest glance of a dragonfly out of the corner of my eye.
Yellow irises by Claude Monet (painted 1914-1917) (Public Domain)
And finally, a poem. I think a lot of us are coming back to the sounds of nature during the lockdown, hearing the birds singing early in the morning, and the thrum of bees. Sadly, here in East Finchley the builders are back and the road (which was closed for some sewage works) is now open, so the rumble of vans is ever present. Nonetheless, things are still quieter than they were, and I find myself quieter inside too. I hope that you enjoy this as much as I did.
Glencolmcille Soundtrack by Moya Cannon
All day long, as I climbed,
in sunshine, up to the holy well,
then on to the Napoleonic watchtower,
and halted behind it, on a headland
tramped brown by sheep, to watch the sea
carve slow blue paths through cliffs and skerries,
May’s soundtrack played on and on-
bee-hum, the high meheh of hill-lambs,
the lifted songs of larks in warm grass
and later, near the court tomb in the valley,
the cuckoo’s shameless call.
When did I forget it,
mislay it or roll it up,
this tapestry of sound
which pleasures us
by spilling hawthorn hedges
in whin-scented summer,
as pools of yellow iris
are conjured out of wet fields
and late bluebells, vetch and fern
capture the ditches?
