Origin and Common Names
Euphorbia olowaluana Sherff var. gracilis (Rock) Sherff, commonly known as Olowalu spurge, is a small shrub belonging to the Euphorbia family. The plant is endemic to the Hawaiian Islands, specifically found on the island of Maui. The plant's species, Euphorbia olowaluana, is named after its place of origin – Olowalu, Maui.Appearance
Olowalu spurge is a succulent shrub that can grow up to 3 feet tall. The plant has slender, upright stems with tiny, oval, light-green leaves that grow in clusters at the tip of the branches. The stems' color changes to reddish-brown as the plant matures, making it a visually striking addition to any garden. The plant's most distinct feature is its flower, a small cluster of bright red cyathia that bloom at the tip of its branches.Uses
The Olowalu spurge is mainly cultivated for its ornamental purposes, adding aesthetic appeal to gardens, rockeries, and indoor plant collections. Its hardy nature makes it an ideal addition to gardens in arid areas or in regions facing water shortage, as it requires minimal watering and is drought-resistant. The plant's milky latex, similar to other euphorbia species, contains toxic compounds that can cause skin irritation or blindness when exposed to the eyes or ingested. Therefore, it's essential to handle the plant with care, wearing gloves and protective eyewear when propagating or pruning it. In traditional Hawaiian medicine, the plant's latex was used to treat skin inflammation, wounds, and headaches. However, due to its poisonous nature, its use in medicinal preparations is no longer popular.Light Requirements
Euphorbia olowaluana Sherff var. gracilis requires bright, direct sunlight to thrive and grow properly. It prefers to be in direct sunlight for at least 6-8 hours a day. This plant will not grow well in low light conditions.
Temperature Requirements
For optimal growth, Euphorbia olowaluana Sherff var. gracilis prefers warm temperatures between 60 to 85 degrees Fahrenheit. It can tolerate a wide range of temperatures but it does not do well in cold temperatures below 50 degrees Fahrenheit. Extreme fluctuations in temperature can cause harm to the plant.
Soil Requirements
The plant requires well-draining soil. The soil should be porous and have a good mix of organic matter to encourage healthy growth. A mixture of sand, loam and perlite makes for great soil for the Euphorbia olowaluana Sherff var. gracilis. Whatever soil is chosen, it must be well-drained, as this plant does not tolerate standing water.
Cultivation methods
Euphorbia olowaluana Sherff var. gracilis (Rock) Sherff can be grown outdoors in warm climates or indoors in pots. For outdoor cultivation, choose a well-draining spot with good exposure to sunlight. Sandy or loamy soils are ideal. The plant can also tolerate drought conditions, so avoid overwatering.
If you decide to grow Euphorbia olowaluana Sherff var. gracilis (Rock) Sherff indoors, make sure you put the plant in a well-lit area with temperatures above 60 degrees Fahrenheit. Make sure the pot has drainage holes to avoid waterlogging.
Watering needs
Euphorbia olowaluana Sherff var. gracilis (Rock) Sherff doesn't require frequent watering. In fact, it's known to be drought-tolerant. You should water the plant only when the soil is completely dry. When watering, you should avoid getting water on the leaves or stem as this can cause fungal infections or rot.
Fertilization
During the growing season, you can feed Euphorbia olowaluana Sherff var. gracilis (Rock) Sherff with a slow-release fertilizer every four to six weeks. Alternatively, you can use a balanced liquid fertilizer every other week. However, be careful not to overfeed the plant as this can cause it to grow too quickly, making it susceptible to rot or breakage.
Pruning
Pruning Euphorbia olowaluana Sherff var. gracilis (Rock) Sherff is necessary to maintain its shape and size. Use pruning scissors to remove the dead, diseased, or damaged parts of the plant. You can also remove the top part of the plant to encourage bushier growth.
Propagation of Euphorbia olowaluana Sherff var. gracilis (Rock) Sherff
Euphorbia olowaluana Sherff var. gracilis (Rock) Sherff can be propagated in two ways: by seeds or by stem cuttings. Here is a detailed explanation of these propagation methods:
Propagation by Seeds
Euphorbia olowaluana Sherff var. gracilis (Rock) Sherff produces small, round seeds that are enclosed in a capsule. To propagate this plant by seeds, it is necessary to collect the capsules once they turn brown. Once the capsules are dry, you can open them and collect the seeds. After collecting the seeds, sow them in a soil mix that is well-draining and has good aeration.
Make sure the seeds are not covered too much in soil, as they need light for germination. The ideal temperature range for germination is between 70 and 80 degrees Fahrenheit. Germination usually takes place within two weeks to a month. Once the seedlings have developed a few leaves, they can be transplanted to individual pots.
Propagation by Stem Cuttings
Euphorbia olowaluana Sherff var. gracilis (Rock) Sherff can also be propagated by stem cuttings. This process involves taking a stem cutting from a mature plant and then planting it in well-draining soil. To take a stem cutting, select a healthy stem that is 3-4 inches long. Make a clean cut just below a node, and remove the leaves from the lower half of the stem.
After preparing the stem cutting, wait a day or two before planting it in soil. Plant the cutting in well-draining soil and keep it in a shaded area. Water the cutting sparingly until roots develop. Once the plant has developed roots, it can be gradually moved to a sunnier area and watered more frequently.
Disease Management
Euphorbia olowaluana Sherff var. gracilis is generally a healthy plant that is not very susceptible to diseases. However, there are a few diseases that can affect this plant, including:
- Root rot: This disease is caused by excessive moisture in the soil, which leads to the root system's decay. To prevent root rot, avoid overwatering the plant and ensure that the soil has good drainage. If the disease has already infected the plant, remove it from the soil and cut off any decaying roots before replanting.
- Crown gall: This disease is caused by a soil-borne bacteria called Agrobacterium tumefaciens. It forms nodules or galls on the plant's stems, which eventually kill the plant. To prevent this disease, avoid injuring the plant's stems and roots, sterilize pruning tools before use, and remove infected plants and soil from the garden.
Pest Management
Euphorbia olowaluana Sherff var. gracilis is a hardy plant that is relatively pest-resistant. However, some pests may occasionally feed on the plant, including:
- Spider mites: These tiny pests suck sap from the plant's leaves, causing yellowing, wilting, and webbing on the plant. To control spider mites, rinse the plant with water, use insecticidal soap or neem oil, or introduce natural predators such as ladybugs to the garden.
- Mealybugs: These soft-bodied insects feed on the plant's sap and produce a white, cottony wax that covers their bodies. To control mealybugs, remove them from the plant with a cotton swab dipped in alcohol, spray the plant with insecticidal soap or neem oil, or introduce natural predators to the garden.
- Caterpillars: These larvae of moths or butterflies feed on the plant's leaves, causing holes and damage. To control caterpillars, handpick them from the plant, introduce natural predators such as birds or beneficial insects like parasitic wasps to the garden, or use organic pesticides that are safe for the plant and the environment.
