Sweet Plum Bonsai Care Guide
This shrub is a native of warm regions in North America as well as Asia and is either semitropical evergreen or deciduous depending upon the climate where it resides. Sageretia theezans may also be called Chinese Bird Plum, Poor Man's Tea, and Chinese Sweet Plum. Bonsai versions are cultivated and exported extensively by China.
This species has tiny leaves, just ¾ of an inch, which grow symmetrically and are ovate and shiny. New foliage growth is a red-bronze color before maturing to green. The bark is dark brown, exfoliating, and scaly, becoming multi-colored over time. Tiny white flowers appear in clusters in summer, and are followed by tiny blue to black fruits.
Sageretia is not a full-time outdoor plant unless in zone 8 or higher. It needs protection once nighttime temperatures fall below 55° Fahrenheit, preferably indoors. Once indoors it should still be permitted to cool down at night.
This plant should ideally have full sun in the morning and shade in the afternoon when outdoors, and when indoors should have bright light but not directly through glass in the heat of the afternoon. In the winter, light levels should be reduced for 6-8 weeks to allow the plant to rest. Good air flow inside will help keep whitefly and mildew away.
Sweet Plum requires well-draining soil that is kept consistently moist but not soaking wet. It is important not to let this plant dry all the way out as that could kill it. It may recover from mild wilting but it's better not to take that chance. If the topsoil feels dry, give the plant a thorough watering. You will develop a schedule once you get used to how long it takes for the soil to indicate that it's time to water.
Commence bi-weekly feeding as soon as fresh growth appears in the spring. Continue this feeding schedule throughout the summer, decreasing to once a month in winter. This is an acid-loving bonsai with a pH preference of 5.5. Adding peat to the soil and using an acid fertilizer like Muracid can be beneficial to this species.
Styles – this is truly a versatile tree, taking well to almost any classic bonsai style, including formal and informal upright, slanting, cascade, and pen-jing.
The propensity of S. Theezans to back bud makes it easy to shape this tree through pruning. Shoots on younger plants should be allowed to grow to at least 4-6" before pruning to shape, in order to give the trunk some time to develop and thicken.
The dense, profuse growth habit requires frequent trimming to maintain shape. Back budding is prolific and growth is angular and rigid. Only trim a portion of new growth at once, never remove all at one time.
This plant is fairly easy to propagate through either seeds or cuttings. To sow seeds, simply sow during any season (indoors if the weather is too cold), keeping moist and warm as you would most seeds, until seedlings appear.
To root cuttings, simply take softwood or hardwood cuttings during the growing season and place in a glass of water for about two to four weeks.
Sweet Plum bonsai should be repotted in the spring of every other year. It should be done only when the plant is completely root bound and when night temperatures are above the low 60's F. Root pruning may be done at a rate of 30% removal of the root mass. Transplant the tree into an all-purpose soil mix. Remember to water thoroughly after repotting and refrain from fertilizing for at least a month.
Insects/Pests & Diseases
This bonsai can be attacked by the typical culprits such as aphids and whitefly. Aphids can be recognized as miniscule light green insects with soft, pear-shaped bodies, which gather on foliage in clusters. Another sign of aphids (and other pests) is a sticky substance on the leaves; this is "honeydew", which is produced when pests eat the sap of the bonsai. Aside from being a sign of insects, this sticky substance also serves as a food source for fungal diseases.
Whitefly can be seen as tiny white moth-like insects. They are far more likely to invade your home if there is a poinsettia plant around. Some enthusiasts advocate the use of a mixture of five parts water, two parts rubbing alcohol, and a tablespoon of dish soap sprayed on the foliage until runoff happens. This mixture should then be rinsed with a spray of clean water.
Good air circulation is vital when a bonsai is kept indoors. Most plants do not like direct drafts, but overall air flow throughout the house keeps away mildew, mites, and other health problems.