In April and May, the cushion spurge awakens spring fever with its bright yellow inflorescences. This is how to plant and care for.
Profile of cushion spurge:
Scientific name: Euphorbia polychroma
Plant family: spurge family (Euphorbiaceae)
Other names: many-coloured spurge, multicoloured spurge
Sowing time: early spring or autumn
Planting time: spring
Flowering period: April to May
Location: sunny to partially shaded
Soil quality: stony to sandy, calcipholous, moderately nutritious, low in humus
These information are for temperate climate!
Use in: flower beds, stand-alone, planters, borders, flower garden, roof garden, rock garden, potted garden
Winter hardiness: hardy, USDA Plant Hardiness Zones: 6 (-20 °C / -5 °F)
Toxicity: partially poisonous
Bee and insect friendly: Yes
Plant characteristics and classification of cushion spurge
Plant order, origin and occurrence of cushion spurge
The cushion spurge (Euphorbia polychroma) is an easy-care perennial of the spurge family (Euphorbiaceae). The plant species is also known under the botanical name Euphorbia epithymoides and is known as many-coloured spurge or multicoloured spurge. Their home is in Central and Southeastern Europe, in northwestern Turkey and Libya.
Characteristics of cushion spurge
Euphorbia polychroma grows bushy and becomes 40 to 60 centimeters (16 to 24 in) high over the years. Under favorable conditions, the many shoots form a dome.
The approximately 5 centimeter (2 in) long stem leaves appear pale green when they shoot and are finely hairy. In autumn the lanceolate leaves turn reddish-yellow.
The umbel-shaped flowers of the cushion spurge open in April and May. The flattened, terminal inflorescences have bright yellow bracts. In the course of the summer these fade and take on different shades – hence the name polychroma.
In August cushion spurge develops red capsule fruits.
Cushion spurge – cultivation and care
The perennial feels most comfortable in a warm place in full sun. Although it also grows in the shade, but the autumn color is then not so beautiful.
Ideally, the soil should be well-drained, calcareous and slightly dry to fresh. Heavy soil, in which water is stored, should be vigorously worked up with sand. It is important that the cushion spurge does not stand wet and therefore does not suffer from waterlogging.
Planting cushion spurge
If you plant cushion spurge in spring, the distance to the neighboring plants should be 40 to 50 centimeters (16 and 20 in). It comes into its own very well in small groups of three to ten plants.
Water the perennials well after planting. After that, it is no longer necessary to water the plant additionally. You should only give the cushion spurge water during long periods of dry and hot periods – but only a little.
Use cactus fertilizer if you want to provide your perennial with additional nutrients for good growth.
A pruning of Euphorbia polychroma is usually not necessary. If you still want it, you should do it in autumn.
Since the sap can irritate sensitive skin, you should always wear gloves when caring for the plant
Most often, cushion spurge propagates by self-sowing. If you want to propagate them specifically, there are various options. Particularly simple methods that hobby gardeners can carry out relatively quickly are division and cuttings. If you decide to sow, the preparation is a little more complicated. Ccushion spurge should not be planted in depressions. There is a risk that rot will occur in these areas.
In spring or summer you can cut off cuttings with a sharp knife. Safety glasses and gloves should be worn during this process. So that the cuttings dry at the cut interface, they are left for a few days. Then they are put into loosened potting soil at a selected location and lightly watered.
In addition to cuttings and sowing, there is also the option of propagating cushion spurge by division. For this purpose, one carefully digs out the root ball of the plant. Afterwards it is split with a knife or by hand. Care should be taken not to unnecessarily damage the roots. It is important to choose rooted cuts. This allows them to grow faster in a new location.
If you decide to propagate by sowing, you should pay attention to controlled conditions. It is not recommended that sowing take place directly in the bed. The reason is that the seeds dry up very quickly. They are also often eaten by snails, birds or other animals. Since cushion spurge need cold to germ, they can be sown very early in the year. The seeds can be kept at a maximum temperature of 5 to 10 °C / 41 to 50 °F until they germinate. Experienced hobby gardeners put them in a plastic bag filled with a culture substrate or damp sand. This bag is kept in the refrigerator, but must never be put in the freezer or in the deep freezer. During this time you have to make sure that the potting soil does not dry out and that it remains slightly moist. If the substrate dries out completely, there is no chance of germination. As soon as the first leaflets appear, the seedlings can be pricked out, placed in pots and taken outside. They grow continuously over the next few weeks.
Diseases and pests
Pests largely avoid the plant. Even snails stay away from this plant.
The cushion spurge can only get sick from root rot. Therefore, you should act wisely and only plant in well-drained soil.
Cushion spurge is commonly known as hardy down to -20 °C / -5 °F. However, various circumstances can endanger the perennial during the cold season. The winter sun can lead to more moisture evaporating from the soil and the perennial. Before the first frost, therefore, cover the plant with fir branches. In early spring, take off the winter protection again. So there can be no rot.
Use in the garden
The sturdy perennial cuts a fine figure individually or in small groups and is ideal for rock gardens, borders and the light edge of woods. Suitable neighbors are, for example, the Siberian bugloss, dittany or bulbous buttercup. Euphorbia polychroma is also a beautiful eye-catcher in the roof garden as well as in buckets and trays.
The leaves of the variety ‘Candy’ – also available in stores under the name ‘Purpurea’ – have a reddish tinge when they shoot and have an intense autumn color. Euphorbia polychroma ‘Bonfire’ is also a bright eye-catcher.