Jeremy Bartlett's LET IT GROW blog

The wonder of plants and fungi.

Wild Tulip, Tulipa sylvestris

Posted on 9 April, 2015 by Jeremy Bartlett1 November, 2018

The first tulips I grew as a child were red Parrot Tulips, which had enormous, brightly coloured flowers with twisted, wavy petals. A kind description of these showy tulips is ‘extremely flamboyant‘, though to the less charitable they could be considered ‘a bit vulgar‘.

I still grow tulips but my favourite at the moment *, which I only discovered this spring, is the Wild Tulip or Woodland Tulip, Tulipa sylvestris. This grows from six to 15 inches (15 – 38 millimetres) tall and has bold, clear yellow flowers.

* I reserve the right to find another favourite tulip at some time in the future.

It is lovely and elegant in bud:

Tulipa sylvestris – in bud

Then it explodes into colour:

Tulipa sylvestris – in full flower

Tulipa sylvestris can be found growing wild in various locations in the lowlands of Britain, where its habitats include open woodlands, orchards, hedgerows, riversides, chalk pits, grassy banks and waste ground. I have never seen it growing in the wild, but have a single plant in the raised bed in our back garden, which I bought from Natural Surroundings in North Norfolk earlier this year. Tulipa sylvestris enjoys growing in a sunny spot and can be naturalised in grass. It is a perennial and has a bulb beneath the ground, to which it will die back after flowering. It is very drought tolerant once established.

Tulipa sylvestris is thought to be originally from Mediterranean Europe but it can now be found in parts of Asia and North Africa as well as Europe. It is hardy in our climate and it was being cultivated in Britain by 1596 and was recorded from the wild by 1790. It was widely naturalised by the late 18th and 19th centuries but has since declined, though populations can persist even if the plants don’t flower [reference].

The Plants For A Future website warns that the bulb and the flowers have been known to cause dermatitis in sensitive people – florists in particular can develop a rash known as “tulip fingers” or “tulip finger disease“.

Tulips are edible – with caution. Plants For A Future says up to five Tulipa sylvestris bulbs a day can be eaten without ill-effect. I have not tried eating tulips, though they have been eaten in times of famine, in particular in The Netherlands in 1944 – 1945. The excellent Eat The Weeds website provides more details of tulips’ edibility. In particular, the skin and the centre of the bulbs should be avoided and most types should be cooked. The petals are edible, though the flavour varies and the ends of the petals can be bitter.

The name ‘tulip’ comes from tulband, Turkish for a Persian turban, which the flowers were thought to resemble. Alternative names that never caught on included ‘lillynarcissus’ and ‘Dalmatian cap’.

Box, Buxus sempervirens

Posted on 19 March, 2015 by Jeremy Bartlett19 March, 2015

“A drab, malodorous and not especially useful shrub” – Richard Mabey, ‘Flora Britannica‘.

Box, Buxus sempervirens, is a slow-growing evergreen shrub or small tree. It is often used as an edging for garden beds and borders, when it is clipped to no more than a foot (30cm) high. But it is capable of growing into a tree and can reach at least 30 feet (nine metres) tall, with a trunk up to 20 centimetres (7.9 in) in diameter. Its evergreen habit makes it a popular choice in churchyards and cemeteries and Earlham Cemetery in Norwich has several specimens, the largest next to the avenue of Lime Trees leading into the Cemetery from the Dereham Road gate.

Box, Buxus sempervirens, in Earlham Cemetery, Norwich.

Box is a British native, a member of the family Buxaceae, which also contains Sarcococca (Sweet Box) and Pachysandra (Japanese Spurge), both of which are useful garden evergreens.

In the wild, Box grows on limestone and chalk in the south of England, often on steep slopes, and is often found associated with beech. It is now found in many parts of the British mainland, as well as in parts of Ireland, as it has been widely planted. British places named after Box include the famous Box Hill on the North Downs in Surrey, which is our largest area of native Box woodland. Other places include Bixley near Norwich (‘Box woods’), Bexhill and Bexley in Kent, Bix in Oxfordshire and Bexington (‘settlement amongst Box’) in Dorset. However, Boxtead Green in Essex is probably from Boc-hamstede (‘homestead amongst beeches’) and Boxworth in Cambridgeshire may be from Bucc’s worth (‘Bucc’s enclosure’). Further afield, Box occurs in open dry montane scrub, particularly in the Mediterranean region and has been naturalised in parts of North America.

Box wood is yellow, very hard and fine grained. It is the wood of choice for wood engraving. (One of Thomas Bewick’s wood engraving blocks was still sound after 900,000 printings.) It is ideal for small wood turning products, such as chessmen and small pulley blocks, clarinets, tool handles and marquetry. As the name implies, it also makes excellent small boxes.

Box foliage has a distinctive smell, not unlike a tom cat’s urine and my mother-in-law cut down a Box bush near her front door because she didn’t like the smell, especially on a hot sunny day. I don’t mind it – it reminds me of a Box that grew in the garden we had in Scotland when I was a child.

Box flowers in early spring. The flowers are inconspicuous and greenish-yellow, with no petals, and are insect pollinated. They are popular with Hoverflies, and in Earlham Cemetery, Norfolk Hoverfly Recorder Stuart Paston has recorded at least seven species visiting the flowers.

Topiary Box ‘Bee’, Helmingham Hall, Suffolk

The Box Bug, Gonocerus acuteangulatus, is a charismatic insect that used to be very rare and was only found on Box on Box Hill. The good news is that this bug is expanding its range and now occurs widely in the south-east of England and beyond, feeding on other species such as Hawthorn, Bramble, Rose, Yew and Plum, as well as Box. Less welcome for gardeners is the Box Sucker or Boxwood Psyllid, Psylla buxi, which sucks the sap and distorts the shoots. However, regular clipping will remove the affected shoots.

More serious for gardeners is Box Blight, a fungal disease of box leaves and stems caused by two fungi, Cylindrocladium buxicola and Pseudonectria buxi. Cylindrocladium buxicola can affect Sarcocooca and Pachysandra as well as Box. Both fungi make Box leaves go brown and fall, leading to bare patches. In severe outbreaks, it may be necessary to dig out the infected plants and destroy them. There is plenty of advice on the internet: Monty Don describes his troubles with Box Blight and Bunny Guinness describes how to control it. Sensible measures not involving fungicides include not watering the plants from above and clipping box hedges less severely and frequently.

In the garden, Box is also affected by other troubles, such as Box Rust, Box Red Spider Mite and Mussel Scale.

If you want to have a green edge for your borders and beds but want to avoid Box, Ilex crenata is worth considering. At Highgrove Gardens they use Hedge Germander, Teucrium lucidrys, as a hedge. The effect is different but there is the added benefit of more pleasantly scented foliage and flowers that are attractive to humans, bees and butterflies alike.

Further reading:

J. Edward Milner, “The Tree Book”, Collins & Brown, London, 1992
Richard Mabey, “Flora Britannica”, Sinclair-Stevenson, London, 1996.

Euphorbia characias subsp. wulfenii, Mediterranean Spurge

Posted on 8 March, 2015 by Jeremy Bartlett1 November, 2018

Euphorbia characias ssp. wulfenii (spring 2004)

Spring brings many delights, including the acidic lime-green cupped bracts of spurges, such as Wood Spurge (Euphorbia amygdaloides), which I wrote about in April 2012. One of the finest of these is the Mediterranean spurge Euphorbia characias subsp. wulfenii, which is looking lovely at the moment. As an evergreen with tall stems clothed with blue-green leaves it provides interest and structure throughout the year, but in spring the plant shines out from its surroundings, whether the day is sunny or dull.

The ‘bracts’ are actually specialised structures called cyathia (singular: cyathium), found only in the genus Euphorbia, part of the family Euphorbiaceae (spurges). Each cyathium is made up groups of separate male and female flowers and each of these flowers consists of just a stamen (if male) or pistil (if female) and there are no sepals or petals. The cup which is underneath and supports the cyathium is called the involucre and it contains nectaries that produce nectar to attract pollinators.

In the wild, Euphorbia characias grows along the northern side of the Mediterranean Sea from Portugal to Turkey. Two subspecies have been recognised: Euphorbia characias ssp. characias and Euphorbia characias ssp. wulfenii. Subspecies characias has weakly trapezoid dark purple to black nectaries on its involucre; subspecies wulfenii has crescent shaped yellow nectaries with distinct horns.

In the garden, Euphorbia characias ssp. wulfenii is widely grown. It grows 1 – 1.5 metres tall, with a similar spread, and likes well drained soil in a sunny sheltered spot. It used to do well (pictured above) in a fairly sunny sheltered border on loamy soil in our previous garden. In our new garden we are growing it in a sunny south-facing raised bed and in sandy, thin soil under our living room window (pictured below).

Euphorbia characias ssp. wulfenii, growing in a south facing border (early spring 2015).

There are several named cultivars of Euphorbia characias, including ‘Humpty Dumpty’ (a dwarf form, growing to 30cm high), ‘Lambrook Gold’ (to 1.2 metres, with large bracts), ‘Black Pearl‘ (to 90cm, with dark nectaries, so presumably a form of Euphorbia characias ssp. characias) and ‘Portuguese Velvet’ (to 50cm, with very blue-grey foliage).

Euphorbia characias is a fairly short-lived plant, lasting no more than five to seven years. It can decline quite quickly: our first plant was doing very well in 2004, then became rather gappy in 2005 before dying altogether in 2006. The better drained the soil, the longer the plant will live. It also dislikes cold winds. Each upright shoot is biennial and should be pruned to its base in June or July. Pruning not only tidies the plant, it rejuvenates it to some extent, and new shoots will be produced almost straightaway. Use sharp secateurs and wear gloves to protect your hands from the irritant sap. Euphorbia characias will self-seed, but if you have a named variety, the seedlings may not come true.

Euphorbia characias mixes well with other Mediterranean plants. The one growing under our living room window is growing beside a Ceonothus ‘Blue Sapphire’, which has contrasting dark green foliage, flushed with bronze. In the raised bed, low sun-loving plants such as Erigeron karvinskianus continue the interest through the summer and the nearby Stipa gigantea should add height and airy movement when it flowers. It will be a good companion, provided it is given enough room and its leaves don’t cover the Euphorbia. The Australian iGarden website lists some other possible planting combinations. It also reminds me that there is a cultivar with white and green variegated foliage and white bracts called ‘Silver Swan’. I grew it (or a similar cultivar) once but I don’t really like the variegation and the cultivar lacks the vivid acid lime-green that attracts me.

Also in our front garden, we have a Caper Spurge (Euphorbia lathrys), which I wrote about in April 2012, and some Cypress Spurge (Euphorbia cyparissias) and the Myrtle Spurge (Euphorbia myrsinites). I do like spurges and I’m not the only one, as is shown by this article in The Guardian by Ambra Edwards.