How to Grow and Care for the Crested Euphorbia (Euphorbia neriifolia cristata)
The crested euphorbia has the ability to absorb formaldehyde and benzene compounds. It has beautiful emerald-green leaves, and both its stems and leaves are fleshy. Its plant form is elegant and closely resembles the qilin of ancient Chinese legend, hence the name "Jade Qilin." The jade qilin likes abundant sunlight but also tolerates partial shade, and it will not die of dryness if slightly drought-stressed, making it suitable for potted indoor viewing. Many people think this is a leafy member of a primitive group of cactus-family plants, but this is incorrect; this ornamental plant is a fasciated (or cristate) variant of the Euphorbia neriifolia, a succulent in the Euphorbiaceae family, which is easy to tell because the base of its spines lacks the areoles unique to cacti and the plant has white milky sap. Family: Euphorbiaceae.
Growing methods and precautions
1. Light The crested euphorbia likes light. After being brought outside in early May, first place it under a shade frame for 7 to 10 days, then keep it in a spot with abundant sunlight. Insufficient light easily causes the abnormal stems to grow leggy and become columnar. Especially during the growing season, be sure to provide sufficient light, and never leave it indoors for viewing for long periods. Although it is dormant in winter, the plant still carries out photosynthesis to maintain basic life activities, so it should also be placed in a sunny spot; otherwise its leaves will turn yellow and drop.
2. Water The crested euphorbia is fairly drought-tolerant. Normally, water it according to the principle of preferring dry over wet. When the potting soil is dry, hard and pale, and a clear ringing sound is heard when tapping the pot wall, water thoroughly. Water less in winter than usual; in a room at 15°C to 18°C, watering thoroughly about once every 10 days is enough. Overwatering not only easily causes reversion but can also suffocate the root system and kill the plant.
3. Fertilizer The crested euphorbia does not much like fertilizer. The principle for feeding is to prefer less over more, and prefer dilute over concentrated. The potting soil can be made by mixing leaf mold, coal cinder, and garden soil in equal thirds by volume, and when potting, add a small amount of crushed solid fertilizer as a base fertilizer. During the growing season, apply once a month a fully rotted alum fertilizer water at about 15%. When fertilizing, never use raw or concentrated fertilizer, otherwise root rot and leaf drop easily occur. In winter during dormancy, fertilization can be stopped, and then gradually resume normal feeding levels when growth begins the following spring.
4. Temperature The crested euphorbia is not cold-tolerant. Generally, it should be brought indoors before the first cold snap arrives before Frost's Descent. At first, pay attention to indoor ventilation and let it gradually adapt to the indoor microclimate. In winter, even if the weather is warm, do not move it outdoors to sunbathe. If the indoor room temperature in winter can be kept above 15°C, the leaves can be kept from dropping; if the leaves have already dropped, as long as the temperature is above 7°C it can overwinter safely. By the following May, it can also grow leaves again. It should be noted that the crested euphorbia is a toxic ornamental plant.
5. Cutting propagation The crested euphorbia is propagated by cuttings. In May to June, select robust abnormal stems, cut them off with a sharp knife, and dry the sticky sap at the wound. After two or three days, dip them in plant ash and insert them into moist sandy river soil to a depth of 3 cm to 4 cm. Press the soil firm by hand and do not water. After 2 to 3 days, spray water again. Spraying only needs to keep the sandy loam slightly moist. After about one month, roots will form, and then they can be potted.
Precautions The crested euphorbia likes dryness, so never water too much; in summer, it is enough for the soil to be slightly moist. The crested euphorbia is not cold-tolerant; in northern regions it should be moved indoors or into a greenhouse before Frost's Descent in mid-October. When winter temperatures are low, keep the potting soil fairly dry. As long as the room temperature is kept above 15°C, the leaves will not turn yellow; below 12°C, the leaves will dry up and drop. Repot once every 1 to 2 years. When repotting, remove the old soil and pick out decayed roots. After repotting, keep the potting soil moist, first place it indoors for about ten days, and then move it back outside.