The cypress spurge is an ornamental plant native to Europe. Because of its strong tendency to overrun the habitats of other species, this plant is classified as a noxious weed in various states, including Colorado. Although this plant attracts bees and other pollinators, some sections of it are hazardous and contain irritants.
I. Appearance and Characteristics
Euphorbia cyparissias, the cypress spurge, is a species of plant in the genus Euphorbia. It is native to Europe and was introduced to North America in the 1860s as an ornamental plant.
Natural habitat types include dunes, pannes, coastal headlands and grasslands. In North America it is commonly found in the dry, gravelly soil of roadsides, pastures, and meadows. Cypress spurge thrives in open, disturbed areas.
The plant ranges from 8 inches (20 cm) to 16 inches (40 cm) in height. Its petal-like bracts are usually green-yellow, maturing to purple or red from May to August. The mature fruit explodes, spreading seeds up to 5 m (16 ft). The plant also reproduces through lateral root buds, which allow it to spread densely. It can be identified by its leaves, which are small and linear, measuring up to 4 cm (1.6 in) long by only 1 to 2 mm (1⁄32 to 3⁄32 in) wide.
This plant is considered a noxious weed in many places, including Colorado in the United States. Like some other non-native plants, it invades the habitat of native species. It is known to be harmful to cattle and horses, but not sheep. It can be difficult to control. Biological pest control methods have been attempted, involving the release of several European insect species in North America. Certain flea beetles have been effective, but there are concerns about the release of non-native insects into the region.
Parasites of this species include Uromyces pisi-sativi, a fungus.
Anthrenus scrophulariae may frequently be found on this plant. This plant is attractive as an ornamental but its invasive nature makes it necessary to control its spread; its root spread is more invasive than its ability to self-seed.
While the roots have sometimes been used as a purgative, it can be poisonous if taken in quantity, and animals can be poisoned by eating hay containing it. Contact with the sap can cause skin reactions.
WARNING: This plant has several irritants. The milky sap is a skin irritant that can cause burns/blisters in some individuals. Late season mature bracts have tiny hair like barbs. Once they are in your skin can cause mild irritation that can last for years. If you work with this plant use gloves and long sleeves. When you work this plant do not touch your skin with gloves on.
II. How to Grow and Care
Sunlight
Spurges naturally grow in places that have plenty of sunlight, but some species can tolerate partial shade (e. g., Euphorbia amygdaloides var. robbiae). Full sun provides the best environment for spurges. If they are grown indoors, spurges need at least 6-8 hours of direct sunlight every day for proper development.
Temperature
Genus Euphorbia is very large and diverse, so its different species can be found in various habitats, but the majority are well-adapted to a temperature range of -29 to 4 ℃. Many spurges, in spite of having succulent leaves, cannot handle long periods without moisture and need to be watered weekly during hot summer days. Some cactus-like species are well adapted to high temperatures and prolonged dry periods, but most species used for landscaping and decorative gardening require more moisture for proper development.
Watering
Adapted to its native environment’s sporadic rainfall, cypress spurge thrives with moderate moisture and displays a preference for well-drained conditions. This species is drought-tolerant once established, maintaining hydration balance through efficient water storage mechanisms. For optimal growth, watering every week aligns with its natural cycle. Typically found outdoors, cypress spurge flourishes in temperate climates where seasonal rain patterns dictate its watering needs and influence its robust growth cycles.
Soil
Spurges aren’t picky when it comes to soil type. They can grow in a variety of soils. Some species of Euphorbia can even thrive in nutrient-poor soils, requiring only that the soil be well drained. If the soil is full of moisture and is prone to water retention, it will most likely cause root rot.
Fertilizing
Cypress spurge doesn’t require large amounts of fertilizer for normal growth and development. In fact, very little fertilizer is required. As mentioned earlier, some species can thrive even in very poor soils, as long as those soils are well drained. Fertilizer should only be applied when the plants start showing nutrient deficiency symptoms on lower leaves. When the lower leaves turn yellow, it is time to add half-strength liquid fertilizer to the soil. That will keep the plant well fed for several months.
Planting Instructions
Dig a hole twice as wide as the plant’s root ball before planting. Then, turn the container with cypress spurge upside down and let the plant slowly fall into your hands. Place the plant upright in the hole and slowly fill in around the roots with loose and fertile potting mixture, adjusting the planting depth until it is just right. Water it once. Do not overwater, as standing water is not good for the plant.
Propagation
The ideal time for propagating cypress spurge is during Spring, through sowing. Propagation is considered moderately difficult, and success is indicated by strong root development and new foliage growth. Ensure adequate moisture and avoid overcrowding for optimal results.
Transplanting
The perfect time to transplant cypress spurge is during the delightful mid-spring season, as it allows ample time for root establishment before harsh weather arrives. Cypress spurge flourishes in well-drained soils and sunny locations, so make sure to provide optimum conditions for healthy growth.
Repotting
Repot cypress spurge in early spring before growth resumes. This perennial ground cover thrives with more space to spread its feathery foliage and may reach 1ft tall. Choose a larger pot every 2-3 years to accommodate its growth rate. Post-repotting, provide well-draining soil and moderate water to encourage recovery without over-saturation. A friendly reminder: wear gloves when handling cypress spurge to avoid its irritating sap.
III. Uses and Benefits
Cypress spurge is perfect as ground cover for dry, sunny slopes, beds and borders, city gardens, coastal gardens or cottage gardens.
IV. Harvesting and Storage
Some species of Euphorbia can be cut for fresh flowers or foliage, such as snow-on-the-mountain (Euphorbia marginata), Euphorbia fulgens and Euphorbiaformosana. When harvesting cuttings, remember to wear gloves, as the sap can be irritating to the skin. It can be cut from the base of the stem. Soak the end of the cutting in hot water for 10 seconds to stop the milky sap from oozing. The vase life of for the cutting will be about 5-7 days, and some flower food can extend its life.
When the fruits of Euphorbia plants are ripe, they burst and scatter the seeds over a large surface area. In order to harvest all the seeds, the individual fruits or the entire plant must be wrapped in in nylon, gauze, or similar material before the ripe fruit bursts and releases the seeds.