Euphorbia: how to grow and care for these useful, low-maintenance plants

In this atmospheric garden perched on a Provençal hilltop, lime green Euphorbia characias spill over the curved path, making a lovely foil to plantings of Iris pallida and clipped mounds of Phillyrea angustifolia.

Eva Nemeth

Capped with a mass of lime-yellow flowerheads over a long period, spurges (Euphorbia) are must-have perennials. Forming pillows of zinging chartreuse colour, often above attractive whorls of evergreen leaves, they are excellent for complementing flowering plants in the front or middle of the border.

The Euphorbia genus is vast, encompassing 2,059 species, found on every continent, apart from Antarctica. They range dramatically in type and size, from the Christmas poinsettia pot plant to the world's biggest succulent tree, Euphorbia ampliphylla, which is capable of 30 metres. The garden forms are mainly perennials and sub-shrubs that provide mounds of fresh lime, often for months; the wads of eye-catching colour atop their stems are not flowers, but bracts that surround the (usually small, uninteresting) true flowers.

As well as showy bracts, another distinguishing feature of euphorbias is that they all contain a toxic sap. This milky latex deters herbivores and aids the plant in coping with drought by retaining moisture. It also gives euphorbias their common name, spurge (from the Old French espurge, to purge), since it was once used as purgative (don't try this at home).

Although spurges are not well-known wildlife plants, they lure beneficial predators (such as ladybirds, which help to reduce aphids) and can attract the regal spurge hawk moth, which will lay its eggs on the plant.

Bright yellow flowers on a cushion spurge plant, Euphorbia epithymoides

Berghiu Livioara

In the average flower border, the cushion spurge (Euphorbia epithymoides) is an essential plant, forming a wonderful mound of acid yellow in spring that provides the perfect foil for tulips and Anemone pavonina. If you can find it, 'Major' is an excellent variety.

The horned spurge (E. cornigera) gets going next. Having reddish stems topped with sunny-yellow bracts from May to August and reaching 1.2 metres, it is a good in the middle of the border, as is E. donii, which puts on a show of green-banana inflorescences from June, and late-blooming E. schillingii, which forms an erect clump of green and gold from July.

Reaching 45 centimetres, E. seguieriana subsp. niciciana is great at the front of the border, where its glaucous leaves are topped with chartreuse bracts for months.

Yes – many forms of euphorbia suit dry regions and gravel gardens. They include the Mediterranean spurge Euphorbia characias subsp. wulfenii, a 1.2-metre sub-shrub from the stony hillsides of Turkey, Italy, and Greece. It has impressive clubheads of lime-green bracts in spring and early summer above beautiful glaucous leaves that will be evergreen in milder regions. E. myrsinites is much smaller and stunning atop a wall or at the edge of a sun-baked gravel bed: it has fabulous arms of spiky blue leaves like dinosaur scales that are topped with green-gold bracts in spring and summer.

In the recently revamped Delos garden at Sissinghurst in Kent, designer Dan Pearson has added several euphorbias to the free-draining Mediterranean beds, including E. myrsinites, E. ceratocarpa, and E. characias, as well as imperious E. rigida, a native to the rocky scrub of Greece, Morocco, and Iran, which has architectural candles of blue leaves arranged spirally and sunny bracts in May and June, when grown in sheltered sun.

Our native wood spurge (Euphorbia amygdaloides) is glorious when it glows green gold in the dappled shade of woodland glades and margins in spring. If you have a woodland garden, it provides good evergreen groundcover, even in dry shade. The best garden form is the fresh lime Mrs Robb's Bonnet (E. amygdaloides var. robbiae), which was found in oak woodland in the Balkans and brought back in a hat box by botanist Mary Ann Robb. E. cornigera and E. sikkimensis can also be grown in part shade.

Marsh spurge (Euphorbia palustris)

Naturfoto Honal

Most widely available spurges prefer drier well-drained soil, but the marsh spurge (Euphorbia palustris) is an exception, enjoying sun-baked deep, moist soil, in which its upright stems can reach 1.2 metres. From April to June, the apple-green leaves are topped with chartreuse bracts; the variety 'Walenburg's Glorie' is a warmer yellow.

Most prefer being in the ground, but those that enjoy good drainage can successfully be grown in pots. They include Euphorbia 'Abbey Dore', which forms a 50-centimetre cushion of acid green for months, and E. myrsinites (mentioned above).

The majority have no smell, but the Canary spurge (E. mellifera) has a lovely scent. This fabulous dome-shaped evergreen shrub for mild regions and urban microclimates is capped with fawn flowerheads that fill the air with a honey scent in late spring and early summer.

Yes – most garden euphorbias are perennials, but Euphorbia oblongata is usually grown as an annual. It will seed itself around the garden, but the seedlings are not difficult to remove.

E. griffithii 'Dixter'

Ottochka

Yes, some spurges (such as Euphorbia donii and E. palustris) take on fiery red tints in autumn; a few have red foliage (for instance, Miner's Merlot), and E. griffithii 'Dixter' has tangerine flowers.

Euphorbia ceratocarpa is an upright 1.5-metre evergreen sub-shrub from Sicily and southern Italy that has blue-green leaves that are paired with yellow-green bracts over an incredibly long period – sometimes all year in milder regions.

Most garden euphorbias (including Euphorbia epithymoides, which grows in stony scrub in Turkey) appreciate free-draining earth.

The majority of spurges are sun worshippers. The more tender species (including E. ceratocarpa, E. characias, and E. mellifera) demand sheltered sun and perform best in the milder parts of the country.

Some spurges (such as 'Abbey Dore') can be grown in containers. Mix John Innes No. 3 compost with grit and sit your planter on pot feet.

Always wear gloves and goggles to cut euphorbias back because they contain a milky sap that can irritate and blister skin and severely wound eyes. Herbaceous perennial forms can be cut back before winter. Take out the flowered stems of E. characias at the base, leaving new stems to flower the following year. Cut off the spent flowerheads of E. amygdaloides in early summer. Some gardeners treat the tender E. mellifera as a perennial, cutting the older stems down to the ground in the spring.

Rarely necessary, as many euphorbias thrive in poor, light soil.

A few euphorbias can be a nuisance. The spreading E. cyparissias, for instance, produces runners under the soil and can be hard to remove. E. amygdaloides is not as much of a menace, but it does spread, so suits medium to large woodland gardens.

This can affect some euphorbias, such as E. amygdaloides 'Purpurea'. To prevent it, avoid planting in sheltered sites and mulch annually with leafmould or compost to boost moisture.

E. oblongata, grown as a hardy annual, can be sown direct in August or under cover in September for bigger plants; alternatively, sow under cover in early spring or sow direct in April or May. Sow shallowly.

E. oblongata

Sundry Photography

E. oblongata is best for cutting. Its bracts are a bright acid green and it stands upright in the vase, making it superb as filler foliage. Wear gloves when harvesting because the cut stems will drip a toxic white sap; dip the stem ends in just-boiled water for 5 to 10 seconds to halt the sap flow.