Portulacaria afra bonsai are attractive, semi-evergreen, succulent bushes or small trees in the family Didiereaceae and the genus Portulacaria. This bonsai is known under several common names, such as Dwarf Jade, Elephant Plant, Elephant’s Food, Small Leaf Jade and Lucky Money Tree. Other common names for this plant are Purslane Tree, Porkbush, Spekboom or “Fat Pork Tree,” and Oligantskos (in Afrikaans). The plant’s name Portulacaria is made up of two words—“Portulaca” (a name of another plant genus, meaning “a little door”) and “aria,” indicating a similarity between these two botanical genera. The word “afra” is a reference to the African origin of the plant.
This indigenous plant is native to South Africa where, in its habitat, it can grow up to a height of three to four meters. It thrives on rocky slopes and dry river valleys. It has been reported that the tree makes up a large part of the elephants’ diet in some South-African regions. Entire countryside regions in South Africa have been named “Spekboomveldt” after the plant which grows in abundance.
Portulacaria afra is a fleshy and softly woody plant with thick trunk and a fine branch structure. The color of its bark changes from green (when the plant is young) to reddish-brown (when the three reaches its maturity) to grayish (when the plant is older). The leaves are small, luscious, circular-to-oval and fleshy, opposite, and have a diameter of approximately two centimeters. Only mature specimens blossom, and the blossoming can happen only after a dry summer season. It sometimes take over a decade for the tree to blossom. The plant blossoms in autumn, and the flowers are small, either white or pink-to-purple and star-shaped. The flower nectar attracts many insects and birds.
Portulacaria afra is an edible plant, with sour flavor. Tender new leaves are used to garnish salads and soups. Rural communities have used the plant in traditional medicine to treat various skin conditions, sore throat, mouth infections and heat stroke. Interestingly, it has also been reported that the plant has ability to absorb efficiently more carbon from the atmosphere compared to other plants, due to its two distinct photosynthesis pathways. Due to this unique characteristic, Portulacaria afra can be deployed as “carbon sponge” in the battle against climate change.
As a cultivates species, Portulacaria afra has worldwide distribution. As a bonsai tree, Portulacaria afra specimens are is typically 20–30 cm tall, and can have a lifespan of up to 200 years. This guide provides the foundations of Portulacaria afra bonsai tree care.
How Long Does It Take to Grow Portulacaria afra Bonsai?
Portulacaria afra is a popular bonsai species since it has the reputation of an easy-to-grown, non-demanding plant. The plant grows fast, and within a few years it can develop dense and attractive foliage. However, training the Portulacaria afra bonsai in a specific style, thickening the trunk and even waiting for the first blooming of the tree can take many more years of patient care.
How to Plant and Grow Portulacaria afra Bonsai?
Propagation
Portulacaria afra propagates by cutting of branches or entire leaves during the summer. It is sufficient to take a small cutting, remove the leaves from the lower part of the stem and let it dry for a fews days. The cutting should then be dipped in rooting hormone and placed in a potting mix. Alternatively, the plant can also be grown from seed.
Temperature Requirements
While Portulacaria afra bonsai can conveniently be kept indoors, it needs exposure to fill sun, near a fully-lit window. The development of red edges on the leaves is a good indicator that the plant is receiving sufficient sunlight. In summer, the bonsai should ideally be kept outdoors in full sun. During the winter period it must be sheltered, since it has very low tolerance to low temperature and frost.
Soil and Watering Needs
The Portulacaria afra bonsai does not need regular watering since it holds large amount of water in its trunk and leaves. It is sufficient to water the plant once every two weeks, although the plant can survive even with less frequent watering, especially in winter. Overwatering can be particularly harmful to this plant, as it quickly rots the roots and kills the plant.
It is recommended to allow the soil to get almost completely dry before the next round of watering. A good practice is to wait with the watering until the leaves of the plant begin to wrinkle a bit as a result of dehydration. On the other hand, if the leaves start turning brown and develop spots, it is a sign that the plant is not receiving enough water. The plant is sensitive to the salt found in regular tap water. Using well-filtered water is much recommended.
Feeding
Portulacaria afra bonsai needs application of fertilizer during the entire growing season, from spring to autumn. Both liquid bonsai fertilizer and a granular feed are good alternatives. The fertilizer should be applied sparingly, once per month. Petroleum-based chemicals should never be used, since they cause major leaf loss. A good choice is organic fertilizer.
How to Care for Your Portulacaria afra Bonsai
The Portulacaria afra bonsai is easy to keep indoor. The plant is suitable for both beginners and advanced bonsai enthusiasts. It is considered an easy-to-grow, low-maintenance, hardy and drought-resistant plant, that grows and develops fast, and can be shaped in various bonsai styles. The most suitable bonsai styles are the semi-cascade, cascade, informal upright and groups. Since this is succulent plant, it droops from its weight under the water contained in its trunk and branches. As a result, it is a good candidate for long cascades.
Pruning, Pinching and Wiring
Portulacaria afra should not be trained to develop like a shrub, and it is thus necessary to create enough empty spaces and allow proper development of a tree-like branch structure. Shaping of the Portulacaria afra bonsai using wiring can be a challenging task, since the wire easily cuts into the trunk and the branches and damages them. It is therefore best to opt out of wiring. This bonsai, especially when mature, needs to be pinched regularly—once a week—during the growing season. Regular and even drastic pruning is a good alternative to wiring, especially since Portulacaria afra is a fast growing tree.
To stop further growth of a particular branch, its terminal bud needs to be removed. After the new shoots have grown about five centimeters, they can be cut back to one or two sets of leaves. Whenever a branch is removed, making concave cuts should be avoided, since they can scar the tree and cause die back. It is safer to always leave a small stub which will in time either rub off or fall.
Use of cut paste is not required, since this plant calluses over naturally, or seals itself. Any chemical sealer may cause development of a disease underneath the applicator. Removal of large branches or parts of the roots needs to be done only when the soil is dry.
To make the trunk thicker, some bonsai experts recommend placing the plant in larger pots and adding stone or socks to the soil mix. The plant should be kept outdoors as much as the climate conditions permit.
Repotting
Portulacaria afra bonsai is repotted in spring, once in two to three years, one the roots have filled the entire pot. More mature specimens need to be repotted only once every four to five years. Before repotting, the soil needs to be completely dry. The best soil to use during repotting is a free-draining soil mix, but a standard bonsai soil mix can also be suitable.
If the rootball of the bonsai tree is wired into the pot, extra care needs to be taken, since the site can easily cut through the roots. Using potting mesh can minimize the risk of damaging the roots during this procedure. Not more than a third of the tree mass should be removed. Once the plant has been placed in its new pot, it should be placed in its usual location and not watered before new growth begins. No fertilizer should be applied for at least a month after the plant has been repotted, as the chemicals can burn the new roots.
Pests and Diseases
Portulacaria afra bonsai is susceptible to root rot and mealy bugs. Keeping the plant indoors under poor light conditions weakens it and triggers a chain of problems. The weakened plant is first attacked by mealy bugs which populate the underside of the leaves, suck the plant sap and secrete honeydew. The honeydew then attracts ants, and soon the fungal sooty mould covers the plant. It is therefore important to intervene as soon as mealy bugs are noticed on the bonsai. The procedure is simple: a small amount of water is splashed on the affected area, and then the insects are wiped off using cotton cloth. Rubbing alcohol can be even more effective, especially if the infestation is more serious, and the procedure needs to be repeated several times.