What are the cultivation methods and techniques for the elephant bush (Portulacaria afra)?

The elephant bush, also known as the purslane tree, ginkgo wood, golden-leaf euonymus, and so on, is a perennial evergreen succulent shrub of the genus Portulacaria in the purslane family. Its stems are succulent, ranging from purplish-brown to light brown, with branches growing nearly horizontally. New branches turn purplish-red under conditions of ample sunlight, and green if light is insufficient. It has extremely high ornamental value. Let us take a look below at how to grow an elephant bush well!

The growth habits of the elephant bush

The elephant bush is native to South Africa and prefers a warm, dry environment with ample sunlight. It tolerates drought and partial shade, but not waterlogging. Although it can grow in shady spots, the distance between stem nodes becomes longer, and the leaves become large, thin, and lusterless, which detracts from its ornamental value. It grows best in sandy soil of medium fertility with good drainage and aeration. During the growing season, water the elephant bush according to the rule of “do not water until dry, and water thoroughly when you do,” avoiding water accumulation in the pot. In winter, the temperature is best kept above 10℃. At around 5℃ the plant will not die, but a large number of leaves will drop off.

Propagation methods for the elephant bush

The elephant bush can be propagated during the growing season by taking cuttings from robust, well-developed branches. Before inserting the cuttings, remove the lower leaves and let them dry for a few days until the cut ends are dry, then insert them into a growing medium made of 2 parts leaf mold, 2 parts coarse sand or vermiculite, and 1 part garden soil. After inserting, keep the soil slightly moist. Once rooted, place it in a sunny spot or in partial shade for care, keeping the potting soil moist but not waterlogged. Do not fertilize for the first 2 months in order to promote root growth. After that, apply a diluted, well-rotted liquid fertilizer about once every 10 days, and promptly prune away young shoots sprouting from the base to concentrate nutrients and speed up the growth of the main trunk.

Cultivation methods for the elephant bush

1. Soil: The elephant bush likes loose, fertile, sandy soil with good drainage. You can use a growing medium mixed from leaf mold and garden soil, then add an appropriate amount of river sand to improve soil aeration and help with drainage.

2. Temperature: The elephant bush likes a warm, dry environment with ample sunlight and tolerates partial shade. The most suitable growing temperature for the elephant bush is 15-25℃. It is not cold-hardy, so it needs protection from freezing in winter. The overwintering temperature should be above 10℃, and below 5℃ it is prone to cold damage. In summer, provide shade to prevent scorching by the blazing sun.

3. Light: Although the elephant bush likes ample sunlight, during the high temperatures of summer it needs appropriate shading to prevent scorching by the blazing sun, and attention should be paid to ventilation. In winter, move the elephant bush to a sunny spot indoors to keep the leaves fresh and green. Long-term insufficient light will cause the distance between its stem nodes to lengthen, and the leaves to become larger, thinner, and lusterless.

4. Watering: From spring to autumn is the growing season for the elephant bush, and it can be watered moderately, but water must not accumulate in the pot. In the hot summer, you can spray water around the elephant bush to increase air humidity. In winter, watering should be controlled to keep the potting soil slightly dry. Note that watering the elephant bush should follow the rule of “do not water until dry, and water thoroughly when you do.”

5. Fertilizing: During the growing season, the elephant bush needs a diluted, well-rotted cake liquid fertilizer once every half month, or a diluted fertilizer solution based mainly on nitrogen fertilizer. If the elephant bush is growing too weakly, add a liquid fertilizer containing potassium. Fertilizing the elephant bush should be light and diluted, never thick or concentrated. Stop fertilizing in winter.

6. Repotting: The elephant bush can be repotted once every two years in spring, trimming away part of the root system, removing 1/2 to 1/3 of the old soil, and replanting it with fresh growing medium.

7. Pruning: The elephant bush has strong sprouting ability, so it should be pruned and its buds pinched frequently to maintain a beautiful tree shape. Also, when repotting the elephant bush, you can do a heavy pruning, cutting off weak branches and other branches that affect the tree shape, and trim away part of the root system, then replant.

8. Pests and diseases: The elephant bush is prone to anthracnose damage, which can be sprayed with a 50% thiophanate wettable powder at 1500 times dilution. Pests include whiteflies and scale insects, which can be killed by spraying with a 50% fenitrothion emulsifiable concentrate at 1000 times dilution.

Notes on cultivating the elephant bush

1. Scattering a few soybeans into the soil where the elephant bush is grown can improve the soil and also release nitrogen fertilizer.

2. Remember never to keep the elephant bush indoors for long periods. It is best if the growing medium is mixed with things like sawdust or decomposed charcoal.

3. When watering the elephant bush, pay attention to observation and record-keeping; its root system is fleshy, and too much water easily causes rot.

4. In winter, keep the room temperature for the elephant bush no lower than 10℃ so it can overwinter safely. At around 5℃, a large number of the elephant bush's leaves will drop off.

5. The elephant bush likes ample sunlight, so you can let it bask in the sun more, but the sunlight must not be too intense; about three hours a day is enough.