Prostrate sandmat (Euphorbia prostrata) is a plant species native to tropical regions of North and South America and the central United States. Prostrate sandmat has spread all over the globe and is considered an invasive species. This resilient plant often sprouts up through cracks in asphalt on roadsides.
I. Appearance and Characteristics
Euphorbia prostrata is a species of spurge known by the common name prostrate spurge or prostrate sandmat.
It is native to the Caribbean and certain parts of South America. It is widely naturalized in many other parts of the world, where it can be found in varied habitat types and in many areas grows as a roadside weed.
Euphorbia prostrata is an annual herb producing slender prostrate stems up to approximately 20 centimetres (7.9 in) long, sometimes purple-tinted in color. The oval-shaped leaves are up to one centimetre (0.39 in) long with finely toothed edges.
The inflorescence is a cyathium less than two millimetres (0.079 in) wide, with white petal-like appendages surrounding the actual flowers. There are four male flowers and a single female flower, the latter developing into a lobed, hairy fruit one to two millimetres (0.039 to 0.079 in) wide.
E. prostrata is similar to both Euphorbia maculata and Euphorbia serpens, but is often hairy on the leaves and stems, while the latter two species are often smooth. It differs from E. maculata by its less elongated and less lanceolate leaves. E. serpens by contrast have much more rounded leaves than E. prostrata with relatively larger and more conspicuous flowers. The flowers of E. prostrata do not typically show the white “petals” seen in E. serpens or E. maculata and thus flowers are hard to detect in the former species. Only E. maculata shows dark spots in the center of each leaf, but this is not always present in that species.
Euphorbia prostrata can be toxic if one is exposed to its latex, a milky white thick liquid. According to the Indian Journal of Ophthalmology, latex from this plant can irritate the eyes and skin. The exposure can even cause intense inflammation of the eye and skin. This sap or latex keeps herbivores away but can also be a problem for those growing this plant. According to a horticulturist, the skin that is exposed to the sap can become photosensitive, and if someone handles it without gloves in the sun, they can end up having blisters.
If someone’s hand comes in contact with the sap, they should wash it with water and soap to make sure the sap is washed off completely. If it enters the eyes, it can cause conjunctivitis and, in extreme cases, blindness. You should consult a doctor if your eyes are exposed.
However, reasonable precautions like always wearing gloves and goggles when handling Euphorbia prostrata can prevent any harm.
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
Prostrate sandmat needs regular watering about once a week, especially during growing seasons. The plants don’t need great amounts of water during temperate environmental conditions, but during hot summer days they need as much water as any other plant. Prostrate sandmat needs to be watered when the planting medium is dry for 5 cm at the surface. Those grown in indoor environments also need a sufficient amount of moisture during the resting season. To avoid excess moisture in the medium, it is best if small amounts of water are added from below.
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
Prostrate sandmat 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
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.
Pruning
In early spring, if there are any damaged stems, they need to be removed to keep the plants healthy and to optimize their nutrient management. It is advised to cut back a certain number of stems after blooming in order to stimulate consistent flowering and growth of new foliage. When cutting a stem, cut at the stem’s base. It is very important to use gloves while handling and pruning prostrate sandmat, because their tissues contain milky-white latex sap which is poisonous and can irritate the skin.
Propagation
Using seeds
You can grow Euphorbia prostrata using its seeds. However, it is not so easy to get them because the germination of the seeds (beginning of its growth) is difficult. Even when they begin growing, they don’t survive for long.
If you can get the seeds, then this is the method:
- Take coarse sand and an equal amount of seed growing mix available in the market.
- Sow the seeds in this mixture. The best time for this is spring.
- In warm weather, germination can take 1 to 2 weeks. However, in cold weather, it can take 2 to 6 months. Therefore, it is better to do it when it is warm.
Using cuttings of the plant
The usual way of growing this plant is propagation. It means you use a part of the Euphorbia prostrata to grow a new one. However, the plant oozes latex when cut. This latex is a thick white liquid that can cause irritation to your skin if it comes in contact with it. So, wear gloves when doing this. Cutting is also useful as pruning the plant can ensure healthy growth.
Here is how you can do it:
- Take a clean knife or any tool you use for cutting and cut a branch. Clean the tool to avoid touching the latex.
- Take the cut stems and let them dry for 2 to 3 days. Allowing these to dry will prevent the formation of any rot on it and the tissue will be able to form properly.
- Plant these stems in a clean vessel that does not have soil as the medium to grow. Instead, use organic or non-organic material for the growth to start. This soilless material like peat moss acts as a sterile environment. However, if you use soil, there is no surety about what is in it.
- Spray these cuttings very lightly with water regularly. Cover the vessel with a plastic bag or a foil to seal the moisture inside.
- Remove the covering (foil or plastic bag) for 2 hours daily to prevent excess moisture and give enough air to the stems. If you don’t remove the covering regularly, mold can develop and ruin the cuttings.
- Check to see if the cuttings have formed a root system. When they do, you can put them in the soil to be planted.
Pests and Diseases
Any plant can get pests or diseases. Euphorbia prostrata may get infected with mealy bugs, spider mites,… To prevent this, avoid watering the plant too much. Excess moisture can invite these issues. If the plant is already infected with diseases, use pesticides.
III. Uses and Benefits
The extract of Euphorbia prostrata is used to treat hemorrhoids. It is because it can stop the bleeding by shrinking the blood vessels. It is also an antioxidant, analgesic, and anti-inflammatory. It has tannins, flavonoids, and phenolic acid that give anti-inflammatory properties which help relieve the inflammation and pain from hemorrhoids.
The extract is available in medicated form as tablets. This medication is also useful for treating varicose veins, bronchitis, and asthma. A doctor can advise the right usage for it. Using the plant directly has limited research. You should be careful using it as it is.
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.
