Euphorbia, Spurge

Euphorbias come in all shapes and sizes, from tiny golf balls to spiny shrubs. They add striking architectural forms, excellent contrasts and flashy summer colours.

Recommended varieties

The following perennials are best grown in borders, where they have plenty of impact, adding bulk and colour to any display.

E. griffithii 'Fireglow': one of the few euphorbias with orange-tinted bracts and a red flush to its leaves. 'Dixter' has leaves with a dark red tinge that make a sumptuous combination with its apricot-coloured flowers. They both give a strong autumn display, before resting over winter. The Royal Horticultural Society (RHS) has handed ‘Fireglow’ its Award of Garden Merit (AGM).
E. schillingii : the vigorous stems shoot up each spring, creating a sizeable mound topped with large heads of yellow flowers. Each lance-shaped leaf is elegantly picked out with a noticeable white midrib. The RHS has given it the AGM.

Evergreens for containers

The evergreen euphorbias are well worth highlighting in large ornamental pots, making first-rate focal points.

E. characias : one of the most popular euphorbias, it's a sun-loving, shrubby plant which, in a large pot, will hit 1.2m (4ft) high. It produces a huge, almost cylindrical head of dark-eyed flowers from late spring to summer. The bracts give a long-lasting display, even when the flowers have gone to seed. There are several good forms including subsp. wulfenii , 'Purple and Gold' with purple-tinged foliage and red stems, 'Blue Hills' with greyish-blue leaves, 'Humpty Dumpty', which is compact and free-flowering, and 'Lambrook Gold', renowned for its good-sized flower heads. The RHS has also given subsp. wulfenii and 'Lambrook Gold' its AGM.
E. mellifera : The plant's large, green, arching and lush leaves smother its numerous stout stems. The sweet aroma from its flowers, produced only in hot summers, has been likened to honey, and attracts a multitude of insects. In mild Cornish gardens, it can be seen to form huge, rounded bushes, over head high. This is still small compared with those found growing in its native Canary Islands, where it can reach tree-like proportions. Being slightly tender, it's best grown in containers so it can be moved to a mild, sheltered position over winter. It has AGM accreditation.

Dwarf euphorbias

E. myrsinites : a tiny evergreen euphorbia, just 10cm (4in) high and 30cm (1ft) wide, that enjoys a dry, baking position and is very effective at sprawling over a dry stone wall. Its greyish leaves are slightly succulent and triangular-shaped, and packed right around the stems - good fun. It's been given the AGM.
E. rigida : similar in appearance to E. myrsinites , but growing twice as big - with upright, evergreen stems and a handsome clump of sea-green leaves.

For shady areas

Some euphorbias can thrive in the darkest recesses of the garden, such as under a heavy tree canopy.

E. amygdaloides var. robbiae : a popular variety grown in difficult, sun-less places, it makes excellent evergreen ground cover. The variety's dark green rosettes of foliage (‘Purpurea’ has purple foliage) on short stems send up large, upright heads of flowers in spring. Like E. characias , the stems then die back to be replaced by new shoots carrying next year's blooms. E. amygdaloides var. robbiae : is native to woodlands in southern Britain. The RHS has given E. amygdaloides var. robbiae : its AGM.

Growing tips

Site and soil preferences

The above like light, free-draining soil with plenty of sun. E. amygdaloides , E. griffithii and E. schillingii need moister, richer ground with a bit of shade.

Division

All hardy euphorbias that die back in winter can be divided in early spring as the new growth starts to emerge. Shrubby or evergreen forms can be boosted by cuttings taken from young shoots in early summer, being grown on in a cold frame or greenhouse. To prevent excessive loss of the white sap when cut, insert the cutting into a pot of gritty compost immediately.