Fukien tea bonsai

Placement

Ehretia microphylla, still sold as Carmona retusa or Carmona microphylla, grows wild from southeastern China and Taiwan to India and Southeast Asia. Its common name refers to the Chinese province of Fujian (Fukien), where it is highly prized for penjing. In a temperate climate it is an indoor bonsai for most of the year; it can live outdoors year-round only in very warm climates.

It needs a lot of light: set it right next to a bright window and add a grow light if light is lacking, especially in winter. A lamp hung about 6 in above the tree can stay on for up to twelve hours a day. Avoid continuous direct sun, however: indoors, about one hour of full sun a day is enough; outdoors, give it morning or late-afternoon sun only.

Warmth should stay as steady as possible, ideally within 59–77 °F and around 68 °F. Never leave it below 54 °F for long: a greenhouse used for overwintering must be heated to at least that temperature, and any winter shelter must let in natural light. When you air out the house in winter, do not expose it to cold or freezing air from an open window.

During the warm months it benefits from a spell outdoors, as long as nights stay warm and the transition is gradual. To bring it back in, go in stages: first a few days in a spot cooler than its summer place, then a relatively cool room in the house, before its winter spot.

It likes high humidity. Heating dries the air in winter, so stand the pot on a large tray filled with gravel or clay pebbles kept moist.

Soil mix

The soil must both drain well and hold moisture, because the tree dislikes drought as much as excess water. A mix of akadama with a little organic matter and pumice works well. Root rot in compacted, soggy soil is the most common problem. Imported trees often come planted in clay that compacts very easily: replace it with a proper bonsai soil at the next repotting.

Watering

Keep the root ball moist without leaving it constantly wet. Ignore labels that say to water every day: water by observation. As soon as the soil surface dries, water generously, then never leave water standing in the saucer. Shriveling leaves are a sign of thirst: water right away. If the dry spell lasts, they turn black and drop, and regrowth takes one to two months. Conversely, general yellowing of the foliage often points to overwatering or poorly draining soil. One symptom can have several causes, so always check how moist the root ball is.

Hard water can cause chlorosis, which turns the leaves yellow; prefer soft water and treat chlorosis with an iron fertilizer.

Fertilizer: its sensitive roots do well with solid organic fertilizer. Use liquid fertilizer at a measured dose and only on soil that is already moist. Feed every two weeks from spring to fall and once a month in winter, and skip feeding for two weeks after repotting.

Pruning

Fukien tea handles pruning very well, and regular trimming builds dense branching. Thanks to its compact habit, it can be shaped by pruning alone, without wire. Hard pruning can be done at any time, as long as the tree is healthy. Its leaves are naturally small, so there is no need to defoliate to reduce them.

Older twigs are hard and brittle, so use suitable, sharp tools. In rare cases, a fungus enters through a fresh wound and can kill a single branch or even the whole tree: work with clean tools and seal every fresh wound with cut paste.

For a tree in development, start with a specimen whose trunk is already thick, because the trunk thickens slowly. With age, the light brown bark turns pale gray and develops an attractive cracked look. The white, star-shaped flowers, in small clusters, are followed by small round fruits that ripen red.

Wiring

Wiring is not essential. Young shoots, tender and flexible, are easy to wire; older branches, hard and brittle, must be bent very gently. Leave wire on as briefly as possible, never more than three months in a row, or it will bite in and scar the bark for a long time. Apply it at about 45° and remove it by cutting it at every turn rather than unwinding it.

Repotting

Repot every two years in spring, as growth resumes. The root system is sensitive, so prune roots cautiously and sparingly. Above all, check that the old soil is not compacted clay, which must be replaced entirely.

Fukien tea is propagated from seed, sown as soon as it is ripe, and from softwood cuttings in summer.

Grown well, it has few problems. In poor conditions it attracts spider mites, scale insects and whiteflies. A suitable treatment helps, but the best lasting remedy is plenty of natural light and enough humidity.