Jeremy Bartlett's LET IT GROW blog

The wonder of plants and fungi.

Green Alkanet, Pentaglottis sempervirens

Posted on 27 April, 2017 by Jeremy Bartlett28 April, 2017

Male Orange Tip butterfly on Green Alkanet

Although the past week has been cold and showery, we have had a very sunny and dry spring, with a lot of warm sunshine. Butterflies, bees and hoverflies have loved this weather and we have had many new sightings, on Rose ‘Canary Bird’, dandelions and perennial wallflowers in our back garden and, a short walk away, in Earlham Cemetery.

A star attraction in Earlham Cemetery has been Green Alkanet, Pentaglottis sempervirens. It is a pretty plant on its own, but it becomes more interesting when its flowers are visited by numerous insects.

Green Alkanet is native to south-western Europe and was introduced into British gardens before 1700 and made its first recorded escape into the wild in 1724. It is still increasing its range here, and now occurs in many parts of the British Isles.

In ‘Flora Britannica‘, Richard Mabey describes Green Alkanet as “a pert, bristly, medium-sized perennial”. The plant dies down in late summer but comes into leaf during the winter or very early spring – hence the scientific name sempervirens (“always alive”, or “evergreen”) and the “Green” part of the English name. The word “alkanet” comes from the Arabic word for henna, via Mediaeval Latin, Old Spanish and Middle English. Pentaglottis is from Greek, meaning “five tongues”, which presumably refers to the flower petals.

The leaves of Green Alkanet are fairly similar to Comfrey but are rougher and more bristly with white spots. By April or early May the plant has elongated and produced pink buds which open to beautiful borage-blue flowers with a white eye, which look rather like supersized Forget-me-nots. The resemblance of Green Alkanet to Comfrey, Forget-me-nots and Borage is not co-incidental: these are all members of the Borage family, the Boraginaceae.

It is not surprising that Green Alkanet is doing well. It isn’t fond of acid soils but it will tolerate shade as well as sunshine. Although it often grows in damp places, it is also happy on our local allotment site in sandy loam. It has a deep tap root which is hard to pull up and it is easy to leave pieces behind, which will keep growing. The plant also spreads by seed. Many gardens in the Unthank Road and Earlham Road area of Norwich are full of Green Alkanet and it was a serious weed in the Belvedere Centre garden. The RHS website recommends various strategies to get rid of Green Alkanet but I would urge you to dig up the roots and to stop the plant from seeding, rather than poison your garden with glyphosate. You can put the leaves on the compost heap, but don’t include the roots as they are likely to regrow. Alys Fowler suggests making a weed soup out of it to feed plants. Like comfrey tea, it will smell bad, but act as a great plant food. Wear gloves when handling the leaves, as the coarse hairs can cause a rash, due to structures known as cystoliths made of silicon dioxide and calcium carbonate.

Green Alkanet flowers are edible but rather tasteless and can be used to decorate salads, in the same way as Borage flowers. The plant may have been introduced for a red dye in its roots, although it may have been confused with the similarly named Alkanet, Anchusa officinalis. Clive Stace and Michael Crawley in “Alien Plants” think “it is a bit of a mystery why this species should be grown at all”.

But I think there is a good reason for liking and growing this plant: its wildlife value. If you have space, or in a wild area like Earlham Cemetery, Green Alkanet comes into its own. Its leaves are used by at least two species of leaf-mining flies (Agromyza sp.) and a micro moth (Coleophora pennella). It is also one of the foodplants of the Scarlet Tiger moth.

In Earlham Cemetery, the flowers are attracting Orange Tip and Green-veined White butterflies, hoverflies such as Rhingia campestris and solitary bees such as the Common Mourning Bee, Melecta albifrons and Gooden’s Nomad, Nomada goodeniana.

Scarlet Tiger moth at Hestercombe Gardens, Somerset.

Gooden’s Nomad Bee, Nomada goodeniana, on Green Alkanet in Earlham Cemetery.

Hoverfly Rhingia campestris on Green Alkanet in Earlham Cemetery

Canary Bird Rose, Rosa xanthina ‘Canary Bird’

Posted on 26 April, 2017 by Jeremy Bartlett1 November, 2018

Rosa xanthina ‘Canary Bird’ in our garden.

One of the joys of spring, in our garden and elsewhere, is the Canary Bird Rose, Rosa xanthina ‘Canary Bird’. It was one of my Dad’s favourite roses and we planted a specimen four years ago in our own back garden.

Rosa xanthina ‘Canary Bird’ is a cultivated form of the Manchu rose, Rosa xanthina, which is a wild shrub rose native to central China, where it grows in scrubby areas and on open hillsides. It usually has an upright, arching growth habit and will grow from two to three metres (six to nine feet) tall and spread to become about three metres wide. Its stems are reddish and have reddish-brown thorns with delicate mid-green leaves. Rosa xanthina has semi-double flowers and R. xanthina ‘Canary Bird’ has the same growth habit but its flowers are single and more open.

‘Canary Bird’ is one of the earliest roses to flower, usually in late April and early May, although ours started to bloom by mid April this year. The flowers have a delicate, musky scent. Our specimen bloomed in its first year but it has been more spectacular every year, as it has developed a bigger framework of branches. Sometimes the rose can have a second flush of flowers later in the year, but I haven’t seen this yet.

Rosa xanthina ‘Canary Bird’ is very hardy and can cope with quite dry soils, provided they contain some organic matter. It will grow in a sunny or partly shaded spot. Ours is in an east-facing border in sandy loam and is in sun from late morning to late afternoon during the summer. Although the RHS website lists a number of possible pests and diseases, species roses such as ‘Canary Bird’ are generally trouble-free, unlike sickly Hybrid Tea thoroughbreds. This makes it an ideal candidate for an organic garden.

‘Canary Bird’ is easy to prune and can be cut into an informal hedge where its thorniness will act as a deterrent to intruders. It is sometimes used in municipal plantings and there is a fine stand of it next to the Canaries (Norwich City) football ground here in Norwich.

It is hardly surprising that Rosa xanthina ‘Canary Bird’ has been praised in the gardening press. It was The Guardian’s Plant of the Week in March 2012 and featured in Alan Titchmarsh’s gardening column in the Express in April 2016.

But I have left the best thing about ‘Canary Bird’ until last: it is great for wildlife. A mature specimen will provide nesting places for birds but it is the flowers that are proving to be very popular with insects in our garden, including hoverflies, and bees such as the delightfully named Chocolate Mining Bee, Andrena scotica.

A female Chocolate Mining Bee, Andrena scotica, on a ‘Canary Bird’ flower.

Winter Purslane, Claytonia perfoliata

Posted on 16 April, 2017 by Jeremy Bartlett1 November, 2018

Winter Purslane, Claytonia perfoliata, growing along Christchurch Road in Norwich

Winter Purslane, or Miner’s Lettuce, Claytonia perfoliata, is an attractive edible plant which can be found in winter and spring in many parts of Norfolk. I grow it on my allotment, where my plants are the self-seeded descendants of plants grown from a bought packet of seeds about ten years ago. In the countryside you can find it growing on sandy, disturbed ground, including under hedges on sandy soils, in places that are too dry in summer to support many other plants. This winter I also found it growing at the bases of Lime trees along Christchurch Road in Norwich.

Winter Purslane comes originally from North America, and its alternative name of Miner’s Lettuce comes from its use by miners in the Californian Gold Rush as a preventative of scurvy. In the UK, the plant was introduced into cultivation in 1794. It was first recorded in the wild in 1849 and by 1853 was the most troublesome weed in the Chelsea Physic Garden. It is an annual and it certainly seeds prolifically, but it is shallow-rooted and very easy to weed out by hand. Its leaves turn yellow as temperatures rise in late spring and you will find no sign of it in summer and early autumn.

Winter Purslane’s small white flowers look rather like those of its distant relative Chickweed (Stellaria media, Caryophyllaceae) but Winter Purslane is in a different family, the Montiaceae. (In older floras it is classified as Montia perfoliata, in family Portulacaceae.) The other member of the Montiaceae naturalised into the British Isles is Claytonia sibirica (Pink Purslane or Siberian Spring Beauty), which has pink flowers and comes from from Siberia and western North America. It can be found in damp woods and has a more northern and western distribution than C. perfoliata.

Winter Purslane is hardy but you can have fleshier, larger leaves a month or two earlier if you grow it in an unheated greenhouse.

Winter Purslane has a mild taste with a mucilaginous texture but I enjoy it raw in mixed salads, where it provides a contrast to stronger flavoured ingredients such as Land Cress, Garland Chrysanthemum or Coriander leaves. (I also allow these three plants to self-seed around the allotment.) I include the flowers in my salad too – they taste just as good as the leaves and look interesting. The Plants For a Future website says that the roots can be eaten too, and taste of chestnuts. They must be peeled first, which would be very fiddly. The leaves can also be cooked too but I haven’t tried these last two methods of preparation.

As well as providing Vitamin C to prevent scurvy, the plant has mild diuretic and laxative properties and can be used as a poultice to treat rheumatic joints. The Californian Superfood Evolution website describes more possible health benefits and has some good photographs of the plant, plus some harvesting tips.

By the way, I don’t recommend harvesting the Christchurch Road plants: they are next to a road and pavement, so the probablilty of contamination by motor vehicle and canine is very high. But seeds are readily available, with instructions, if you want to grow the plant yourself, from Sarah Raven, for example. I think I bought mine from The Organic Gardening Catalogue or Kings Seeds.