Early Crocus, Crocus tommasinianus

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Early Crocus, Crocus tommasinianus

Early Crocus, Crocus tommasinianus

Spring is on its way at the allotment and, as usual, patches of Snowdrops, Winter Aconites and crocuses are providing patches of bright colour, with daffodils to follow soon.

The biggest patches of flowers in February and early March are the Early Crocuses, Crocus tommasinianus. I planted a few corms next to my Tayberry around fifteen years ago and every year the main clump increases in size and is supplemented with smaller outlying patches of flowers. They are usually in flower so early that their only insect visitors are Honeybees and the very first queen bumblebees to emerge from hibernation.

Bombus terrestris queen

A queen Buff-tailed Bumblebee, Bombus terrestris, visiting Crocus tommasinianus flowers. (Photo credit: Vanna Bartlett.)

Here in the British Isles, Crocus tommasinianus is the earliest species of crocus to appear in spring, giving its name of Early Crocus. (They are also known as ‘Tommies’, after their specific name.)

Crocus tommasinianus has delicate mauve to pale purple flowers with a white corolla tube. (You can see this tube in the left flower in the photograph above.) The flowers are accompanied by typical crocus leaves, dark green with a white stripe down the centre (note 1). After flowering the leaves and flowers die back and by mid spring the plant is confined to its corm, with no growth visible above ground.

Crocuses are members of the Iris family, Iridaceae. There are no native crocuses in Britain; they are all neophytes that have been planted or have escaped from cultivation.

Crocus tommasinianus has been cultivated in Britain since 1847 and was first recorded in the wild in 1963. It can be found in open deciduous woodland, in churchyards and gardens, on roadsides, in parks and in amenity grasslands (see distribution map).

Crocus tommasinianus

Naturalised Crocus tommasinianus in Norwich’s Earlham Cemetery.

Crocus tommasinianus is an excellent garden flower, especially in mass plantings. It copes well with hungry Grey Squirrels and Muntjac in our local cemetery (note 2). It grows well in lawns, which should be left uncut until the foliage has died down in mid spring.

Crocus tommasinianus can spread both vegetatively (the original corm splits into a number of “daughter” corms) and from seed. Given the chance, Early Crocuses will form a carpet of flowers. I love this generous habit but some gardeners don’t, which is why the offspring of discarded crocuses can sometimes be found on roadsides.

In the UK it will grow best in a sunny spot on well-drained soil; in the United States the Missouri Botanical Garden suggests “average, medium moisture, well-drained soils in full sun to part shade“. On sandy loam my allotment plants are in full sun but I have some naturalised in grass in the back garden in quite a shady spot. Insects are most likely to visit flowers in a sheltered sunny place.

The natural range of Crocus tommasinianus is in southern Hungary,  north-west Bulgaria, Albania and southern parts of the former Yugoslavia. The plant is named after Muzio Giuseppe Spirito de Tommasini (1794 – 1879), a botanist and politician from Trieste in Italy.

There are a few named varieties of Crocus tommasinianus. The garden designer Non Morris describes several (accompanied by lovely photographs) on her blog, The Dahlia Papers. They include: ‘Roseus’, ‘Bobbo’, ‘Barr’s Purple’ and ‘Ruby Giant’.

I am not certain whether Crocus tommasinianus is edible, so I would err on the side of caution and not eat it. The species certainly isn’t listed amongst the edible varieties Arthur Lee Jacobson describes on his website.

Crocus flowers open wide on sunny days but close up at night and on cold days. They do this by means of a differential growth in responses to temperature, known as thermonasty.

When the flowers warm up the inner sides of the tepals expand more quickly than the outer ones, causing them to open outwards. When the temperature falls, the outer sides of the tepals expand more rapidly and the flower closes up again. A temperature increase of just 0.36°C is enough to start the opening of the flowers. Tulips do this too (note 3).

Notes

Note 1 – There are some good photographs of Crocus tommasinianus on the Wildflower Finder website.

In his Flora, Clive Stace’s key covers thirteen spring-flowering species of Crocus, including C. tommasinianus. (Autumn-flowering species, such as Saffron, Crocus sativus) are mentioned separately.

The other main difference between C. tommasinianus and C. neapolitanus (Spring Crocus) and C. vernus (White Crocus) is the width of the mature leaves, 2 – 3 mm wide in C. tommasinianus and 4 – 8 mm wide in the other two species.

Note 2 – Sandy Leven (on the Scottish Rock Garden Club website) notes that Pheasants can sometimes eat the emerging flowers.  The Lawn and Landscape website says (for the United States at least) that Crocus tommasinianus flowers are pretty squirrel-proof.

Note 3 – Wikipedia’s entry on thermonasty also describes how Rhododendron leaves wilt in cold weather. In tulips and crocuses, the response will protect the flower’s pollen from rain and snow.

Geastrum britannicum (Vaulted Earthstar) – a nice find

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It’s always good to find something new, better when it is unexpected and better still in January, a month that generally comes last in “Best Month of the Year” competitions.

The surprise highlight of a walk yesterday was the Vaulted Earthstar fungus, Geastrum britannicum.

My friend Sarah and I were walking along a minor road just outside Norwich when we both noticed some Earthstars growing on soil on the verge, amongst Ivy, beneath trees. We both spotted the fungi at the same time and I took a series of photos.

Geastrum britannicum

Geastrum britannicum

I wasn’t sure which Earthstar we’d found, so when I came home I shared my pictures on Facebook with members of Norfolk Fungus Study Group. One of the group members, Jonathan Revett, identified them for me as Geastrum britannicum.

Jonathan is very familiar with the species, having found the first specimens on a roadside verge beneath pine trees in Cockley Cley in the Norfolk Brecks, in 2000. The nearest fit appeared to be the Rayed Earthstar, Geastrum quadrifidum, though they didn’t look quite right. In subsequent years, further forays elsewhere in Norfolk and in Hampshire, Powys and Shropshire found more of the unusual fungi. They consistently had small spores (3 – 3.5 micrometres), smaller than all the other British species of Earthstar (note 1).

Samples of the fungi were sent to Kew Gardens for its Mycology Collection and several years later they were looked at by a Spanish team comparing gene sequences in Geastrum, including the PhD student Juan Carlos Zamora (note 2). As a result, in 2015 the fungus was recognised as a new species, and given the name Geastrum britannicum because it had only been found in the British Isles .

When I originally wrote this in January 2021, Geastrum britannicum didn’t have an official name but three years later (February 2024) it is known as the Vaulted Earthstar.

It seems that the species is not necessarily rare, just overlooked (note 3). Specimens in other collections have been checked and the Kew database now contains records from ten different samples, the earliest taken in 1994 (note 4).

I have cycled by the site where we saw yesterday’s earthstars on many occasions without realising that I was passing hidden treasure. It pays to look more closely.

Below are some more of my photographs of Geastrum britannicum. More photos can be found online on Jonathan Revett’s Fenfungi website, in this Business Insider article (also Jonathan’s photos) and on the Nature Picture Library website (photo by Adrian Davies).

Geastrum britannicum

Geastrum britannicum

Geastrum britannicum

Notes

Note 1 – See page 9 in the Herefordshire Fungus Survey Group News Sheet No. 29, Spring 2015. The newsletter gives the background to the discovery and a useful summary of the identification characteristics:

  • Erect, grooved pointed ‘beak’ when fresh
  • Distinct halo around the beak which is surrounded by a rim
  • Sac may be coated with fine mica-like scurf
  • Sac may have a hanging collar-like shape at the bottom
  • Sac is raised on a stalk
  • 4 – 5 ERECT ‘legs’
  • Whole structure standing on a saucer of matted hyphae and debris
  • Habitat: mostly under churchyard yews, but also known under roadside oak and pine.

The news sheet also states that “It is the combination of these characters that is important. If only one or two characters are present, your find may be G. fornicatum, striatum, quadrifidum, or even berkleyii. If you think you have found G. britannicum, examination of the spores is essential as they are smaller than all other UK species.”

Jonathan Revett commented on my photos: “Key features are the arching arms and a fimbriate not beaked mouth which is delimited (halo around base of beak). They also seem to enjoy growing in churchyards often in large numbers”.

Note 2 – See “Integrative taxonomy reveals an unexpected diversity in Geastrum section Geastrum (Geastrales, Basidiomycota)“.  J.C. Zamora, F.D. Calonge, M.P. Martín. Persoonia vol. 34: pp130–165 (2015). The whole paper can be downloaded for free as a PDF (which I wish was possible more often.)

Note 3 – See “Geastrum britannicum – a surprisingly common new species in Britain“. Brian Spooner, Alick Henrici, A. Martyn Ainsworth. Field Mycology, vol. 16, issue 2, pp54 – 57 (2015).

Note 4 – From an online search of the Mycology Collection using “Geastrum britannicum” in the ‘Taxon’ field. All the samples were found growing on soil, sometimes in leaf litter, under a variety of trees.

Rose ‘Aloha’

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Rose 'Aloha'

Rose ‘Aloha’

“The world is a rose, smell it, and pass it to your friends.” – a Persian Proverb (found on Proflowers.com).

We have four roses in our garden. My favourite is ‘Canary Bird’, which I wrote about in April 2017.  We also have a lovely Sweet Briar (Rosa rubiginosa) in the front garden and Rose ‘Allen Chandler’ climbs up Vanna’s studio. The fourth one is Rose ‘Aloha’, which I’ve decided to write about today.

Most of the plants we grow have open flowers with plenty of pollen and nectar for insects, but Rose ‘Aloha’ has closely packed pink petals. It offers little reward for pollinators (though hopefully shelter for earwigs). It nonetheless has a place in the garden because it is a beautiful plant. The flowers have a delicious, rather fruity scent and are produced in May and June. The rose repeat flowers later in the year if you remove the dead flower heads.

Today, the last of 2020, is the coldest of the year here in Norfolk.  But much of December has been mild and wet, so ‘Aloha’ is still in bloom.

Rose 'Aloha' in frost

Rose ‘Aloha’ in this morning’s sharp frost.

Our Rose ‘Aloha’ is now over seven years old.

In July 2013 my friend Rosemary (who sadly died of cancer a couple of years later) drove me out to the Peter Beales Garden Centre on the western edge of Attleborough. We enjoyed many plant hunting trips together and the back of her car was always full of our purchases after a day out. If the nursery or garden centre had a cafe that was an added bonus.

This time we had gone to look at and buy roses – I wanted a couple more for the back garden. Roses can be bought as bare root specimens or as container grown plants. If you want to save money or establish roses in winter, the bare root option is a good one to choose and you may also have a greater range of varieties to choose from. But a visit in summer means you can see roses in flower and sample their flower colour, shape and scent. And I wanted roses there and then – I didn’t have the patience to wait until winter.

I planted ‘Aloha’ in our front garden, hoping it would grow up the trellis by the front door. However, the place I’d chosen was very hot and sunny in summer and had rather limited space for roots. The rose battled on and flowered for a couple of years but it clearly wasn’t happy, so I moved it to the back garden. Its place was taken up by a thriving Chocolate Vine, Akebia quinata, which now provides welcome shade for the front door, as well as flowers and – in 2020 – fruit, although it has to be kept in check if we are to receive any post.

The rose did better in its new home but was a bit too tucked away in a shady corner, so once I had removed our Gunnera manicata (note 1) I moved the rose a few feet out from its wall, so it could climb in front of our large, evergreen Japanese Honeysuckle (Lonicera japonica). It loves its new home, which is sheltered and south facing, but with some shade at its roots.

There are some lessons here about finding the right place for plants. Learn from your mistakes and don’t be afraid to move a plant to a better place if it isn’t doing well or could do better in a more suitable spot in the garden. ‘Aloha’ seems to have finally found a good home.

Rose 'Aloha'

Rose ‘Aloha’ with Lonicera japonica and Clematis ‘Little Bas’.

Rose ‘Aloha’ is a climbing rose. “The Quest for the Rose” by Roger Philips and Martyn Rix (BBC Books, 1993), which I inherited from my Dad, says it is “a superb shrub or low climber”, which is a good description.My plant has reached about seven feet (2 metres) tall and has a spread of about six feet (1.8 metres).

I don’t think it will get much taller in my sandy loam but greater heights are apparently possible: the RHS gives a height of 2.5 – 4 metres (8 – 13 feet) after 2 – 5 years, Peter Beales says 10 feet (3 metres) and David Austin Roses gives a height of 12 feet (3.6 metres).

‘Aloha’ is a Hybrid Tea rose and in my experience these roses often suffer from a whole raft of fungal diseases such as black spot and mildew. However, Rose ‘Aloha’ is has good disease resistance and with dark, leathery foliage my plant has been a picture of good health, in spite of its past ill treatment.

‘Aloha’ dates from 1949 and was raised in the United States by Eugene Boerner (1893 – 1966), who worked for the  Winconsin firm of  Jackson and Perkins. It is the offspring of a cross between roses ‘Mercedes Gallant’ and ‘New Dawn‘ (note 2).

Notes

Note 1 – The Gunnera needed more water than I could provide, especially as it became larger and more impressive. Giving the plant several buckets of water a day was not practical or sustainable in the drylands of Norfolk. Coming home to see a wilting or collapsed giant was not a good end to the day. I dug it up one early spring and divided the crowns into multiple plants and gave them to a couple of friends.

Note 2 – ‘New Dawn‘ has pale pink flowers and is still a popular rose. (David Austin and several other nurseries stock it.) However, my internet searches for ‘Mercedes Gallant’ found cars but not roses. If anyone know more about this variety, please get in touch.