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. 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).

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.