Euphorbia polychroma

Euphorbia give us some of the best early spring herbaceous colour, but Euphorbia polychroma has the most impact. Also known as Euphorbia epithymoides this compact variety grows to only 50cm (20in) with a spread of around 70cm (28in), the plant forms a neat dome. It colours up with a great mound of yellow-green that lasts the best part of a month, fading gracefully for a month or so after.

It is the colour of spring, one that blends easily with a range of colours. It echoes the daffodils and looks good with blue and mauve. It is particularly useful for combining with hardy geraniums where a ground-covering low planting is needed, as it has a similar habit and dimensions but starts flowering at least a month earlier than any of the geraniums.
Like all euphorbias, the colour we see is not that of the flowers, but of the long-lasting bracts that enclose the flowers. In autumn the foliage turns a lovely shade of bronze.

Traditional thinking with plants of such dimensions is to place them at the front of the border, but as long as they are not overwhelmed by neighbours they can be placed further back. The plant is easily forgotten or hidden when its flowering season is over.
Euphorbia polychroma is an easy plant to grow, and it is pleasingly hardy and long-lived. It performs best in full sun, but does well enough in a little shade.

• Awarded the RHS Award of Garden Merit
  Euphorbia polychroma was awarded the Royal Horticultural Society’s Award of Garden Merit (AGM) in 1993.

Sowing: Sow in late spring to early summer.
Soak the seeds for two hours in warm water before sowing. Euphorbia plants do not like root disturbance, so it is best to sow the seeds in place of growth or to use deep plugs or pots. Grow at 20 to 26°C (68 to 78°F) . Be patient, germination is generally very slow, it may occur in two to three weeks at but sometimes can take a few months.

Sowing Direct:
Sow directly where they are to grow, once temperatures have risen and the soil has warmed. Sow on the surface of the soil and keep damp but not wet.

Sowing Indoors:
Surface sow the seeds into plugs or small pots using a good seed sowing mix or well drained soil and cover seed with vermiculite, do not exclude light.
Prick out each seedling as it becomes large enough to handle, transplant into larger pots to grow on. Gradually acclimatise to outdoor conditions for 10 to 15 days before planting out. Plant 30cm (12in) apart in sun and ordinary well drained soil.

Cultivation:
Euphorbia need full sun to partial shade, with a well-drained soil mix. The plants should be well watered and be allowed to dry before watering again. The plants are native to poor soils and do not need fertiliser or excessive water. Too much of either will provide lush growth but at the expense of flowers.
Cut the plants back by about a third after flowering is finished. Doing this will also curb self-seeding. This helps plants stay compact and prevents them from falling apart in the centre, which mature plants have a tendency to do in mid-summer.

Cut Flowers:
To produce longer lasting cut flowers, sear the cut ends over a flame or dip them in boiling water.

Plant Uses:
Borders and Beds. Cut Flowers.

Caution:
As with all members of the Euphorbiaceae, plants and seed are toxic if eaten.
When working with spurges, plants should be handled with care, especially when sap is showing. Always wear gloves since the milky sap is poisonous and a potential skin irritant. The latex is corrosive to the skin and can cause burns or dermatitis.

Origin:
Euphorbia polychroma is native to the rocky hillsides and open dry woodland in south-east Europe and Turkey.
Euphorbia appear as natives across the world and are one of the most interesting and diverse genus, featuring an incredible 2,000 plus widely varying species, including many good garden plants. The plant belongs to the same family as the Poinsettia, Euphorbia Pulcherrima.

Nomenclature:
The genus was named after Euphorbes, the personal physician to the Numidian king Juba II, who is said to have discovered the toxic and curative potential of the white and milky sap in the plant.
The word Euphorbus derives from the Greek eu meaning ‘good’ and phorbe meaning ‘pasture or fodder’ thus giving euphorbos the meaning ‘well fed.’
The species name polychroma means 'of many colours' referring to the bracts that turn from green, to yellow, to red. It is taken from the Greek polys, meaning 'many' and chroma meaning 'colour'
The common name ‘Spurge’ derives from the old French espurgier meaning 'to purge', as the sap of herbaceous euphorbias used to be used as a purgative, a laxative.

The proper botanical name of this species is constantly in doubt. E. polychroma, named by an Austrain, Anton Josef Kerner in 1875, was superseded by E. epithymoides, given by Linnaeus, in 1770.
Normally the first name takes precedence, and thus E. epithymoides should be the correct name. However, that name had been given to another species. Because of this confusion, cushion spurge will be listed by both names for many years to come; choose the one you like and stay with it." (Herbaceous Perennial Plants, 1989)

The name Euphorbia is named for Euphorbus, the Greek physician of Juba II, the King of Mauretania.
Juba was educated in Rome and married the daughter of Antony and Cleopatra.
He was apparently interested in botany and had written about an African cactus-like plant he had found or which he knew about from the slopes of Mt. Atlas which was used as a powerful laxative. That plant may have been Euphorbia resinifera, and like all Euphorbias had a latexy exudate.
Euphorbus had a brother named Antonius Musa who was the physician to Augustus Caesar in Rome. When Juba heard that Caesar had honoured his physician with a statue, he decided to honour his own physician by naming the plant he had written about after him.
The word Euphorbus derives from the Greek meaning ‘well fed.’ Some sources suggest that Juba was amused by the play upon words and chose his physician's name for the plant because of its succulent nature and because of Euphorbus' corpulent physique.
One species of Euphorbia, E. regis-jubae, was named in honour of King Juba II.