Another August, another trip to the Ted Ellis Reserve at Wheatfen (note 1).

One of the highlights of a late summer visit is Small Teasel, Dipsacus pilosus, the lesser known cousin of the Common Teasel, Dipsacus fullonum. There is usually a lovely patch of it beside Penguin Dyke.

Teasels are related to scabiouses, such as Devil’s-bit Scabious, Succisa pratensis, which I wrote about in September 2020. Until recently they were all in their own family, the Dipsacaceae (Teasel family) but they have now been included in the Caprifoliaceae (Honeysuckle family) as a sub-family, the Dipsacoideae (note 2).

Small but Tall

The Small Teasel is less well known than its cousin and has smaller flowers but it often reaches greater heights. In damp soil with a good supply of nutrients, Small Teasel plants can reach at least 1.5 metres (five feet) tall.

Both the Common Teasel and Small Teasel are biennials. Their seeds usually germinate in spring or autumn and each plant forms a low rosette of leaves in its first year of growth, followed by a towering flower head in its second year.

Small Teasel, Dipsacus pilosus, at Wheatfen. 7th August 2023.

Small Teasel, Dipsacus pilosus, at Wheatfen. 7th August 2023.

Small Teasel flowers from late July until early September and each flower head consists of a common receptacle with numerous small, white flowers.

The main stems of Small Teasel are smooth but both the flower heads and flowering stems are spiny.

The spines on the flowering stems are soft but the sharply pointed basal bracts between the flowers are rather sharp.

Small Teasel flowers have four white petals and four white stamens with brown-black anthers at their tips.

The white petals are weakly zygomorphic and the lower petal bends down to form a lip.

Flowers In Detail

Small Teasel, Dipsacus pilosus – flower bud. 21st August 2024.

Small Teasel, Dipsacus pilosus – flower with black-brown anthers. 21st August 2024.

Small Teasel, Dipsacus pilosus – young seedhead. 21st August 2024.

Small Teasel Leaves

The leaves of Dipsacus pilosus change shape along the flowering stem. The basal leaves, produced in the first year, are simple. Further up the stem, they have bluntish but rather irregularly-spaced and shaped sawtooth teeth. The leaves nearer the top of the stem often have a pair of leaflets at their base, as in the photograph below.

Small Teasel, Dipsacus pilosus – leaves. 21st August 2024.

The Wildflower Finder website has excellent pictures of the different leaves and of flowers at different stages of development.

Mike Crewe’s Flora of East Anglia website has very useful pictures of Small Teasel, Wild Teasel and two of their introduced relatives, Cut-leaved Teasel (Dipsacus laciniatus) and Fuller’s Teasel (Dipsacus sativus) (note 3).

Distribution

By now, you’ll hopefully want to see Small Teasel for yourself.

In the British Isles, Dipsacus pilosus is a native of England and Wales, mostly in the lowlands, in the southern half of England. It is a neophyte in Ireland and the Channel Islands (note 4).

Small Teasel prefers damp, calcareous soils.

In Norfolk, Dipsacus pilosus often prefers wetter places, beside ditches, streams and riverbanks. Other than Wheatfen, I usually see it close to the River Waveney, at Syleham, on the Norfolk – Suffolk border (note 5).

Dipsacus pilosus can also be found in the more open parts of woodland – on the edges, in rides and in clearings. It also grows in scrub and hedgerows and in quarries and on waste ground.

Small Teasel relies on soil disturbance for germination of its seeds, and so its appearance can be very sporadic.

Outside the British Isles, Dipsacus pilosus is native in many European countries and as far east as Iran.

Teasels in the Garden

I grow Wild Teasels on my allotment and in my garden and they do well, even on sandy loam. Our summers are typically droughty but the plants still grow tall and flower well. Like Small Teasel, Wild Teasels rely on soil disturbance to self-seed and in winter I transplant seedlings from the allotment to grow in the garden, where there is very little bare soil.

I’ve never tried growing a Small Teasel and I suspect I would need to water it regularly in summer for it to thrive in my garden.

However, if you have moist but well-drained soil (that near-mythical ideal growing environment for so many plants) or poorly drained soil, the Small Teasel should be a lovely addition to all but the most formal, straight-laced garden. The RHS website suggests growing it in sun or partial shade in a neutral or alkaline soil.

It’s possible to buy seeds and plants online. If Small Teasel likes your growing conditions and you let it self-seed you may never need to buy it again.

Do let me know your experiences of growing Small Teasel. I find Wild Teasel is tough and slug-proof and hopefully Small Teasel will be the same.

Visitors

One of the pleasures of seeding Small Teasel at Wheatfen is the variety of insect visitors it attracts, especially bumblebees and hoverflies.

Hoverfly Eristalis intricaria on Small Teasel flower. August 2024.

Hoverfly Volucella pelluscens on Small Teasel flower. August 2023.

Tree Bumblebee, Bombus hypnorum on Small Teasel flower. August 2022.

I often see Goldfinches feeding on the seed heads of Wild Teasel.

Small Teasel seed heads are similarly popular and the Flora of Norfolk says that the seeds are distributed by Marsh Tits and Goldfinches (note 6).

Notes

Note 1 – The Ted Ellis Reserve at Wheafen is a frequent source of inspiration for me, particularly in August when many plants are in flower there and the fen’s lush vegetation contrasts with Norfolk’s otherwise parched landscape.

After previous visits I’ve written about several of its plants, including: Marsh Sowthistle, Sonchus palustris, Common Fleabane, Pulicaria dysenterica, Great Willowherb, Epilobium hirsutum and Broad-leaved Ragwort, Senecio sarracenicus.

If you plan to visit, there is a small car park and there are bike racks behind the warden’s office. Do be aware that no dogs are allowed (bliss!) and check the website because high tides sometimes flood the lower reaches of the reserve, especially in the autumn and winter. At the time of writing, the banner at the top of the home page says “The reserve is currently open as normal – wellies are strongly recommended“.

Note 2 – In Stace’s Flora Dipsacus is still considered to be part of the Dipsacaceae, along with Cephalaria (Giant Scabious), Knautia, Succisa and Scabiosa (scabiouses). Pages 834 – 837, “New Flora of the British Isles“ by Clive Stace, Fourth Edition, 2019.

I must write about Wild Teasel, Dipsacus fullonum, sometime. In the meantime, I highly recommend John Grace’s “Plant of the Week” post for 27th July 2020 on the Botany In Scotland blog.

Note 3 – The Yellow-flowered Teasel (Dipsacus strigosus) has also been introduced into the British Isles and Stace also mentions a couple of hybrids – between Wild Teasel and Cut-leaved Teasel and between Wild Teasel and Fuller’s Teasel. Pages 834 – 837, “New Flora of the British Isles“ by Clive Stace, Fourth Edition, 2019.

Note 4 – The 2020 BSBI Plant Atlas shows it in just one ten kilometre square, on the east coast, south of Dublin.

The Wildflowers of Ireland website has details of a plant found by Zoë Devlin in County Dublin in 2007. (“The jury is still out on this identification. There is a possibility that the plant which I found in Co Dublin is ‘Dipsacus pilosus’ but also that it may be a plant very similar which has come to our shores from further afield than England or Wales where Dipsacus pilosus grows. If/when I get nearer to the precise facts about the plant in my photograph, I will alter this page of the website.“)

In Britain, neophytes are plant species that were introduced after 1492 (the year Columbus arrived in the New World).

Note 5 – St. Margaret’s church, Syleham is worth a visit too, for its history and beauty and  the massive quantity of Devil’s-bit Scabious, Succisa pratensis, in its churchyard.

Note 6 – Gillian Beckett, Alec Bull and Robin Stevenson, “A Flora of Norfolk”.  Privately published, 1999. Page 195.