Cyphomandra betacea Seeds | Tree Tomato

Categories：Tree

Tamarillo (Cyphomandra betacea) bearing clusters of egg-shaped red fruit among large heart-shaped leaves — Tamarillo (*Cyphomandra betacea*): the fruit ripens from purple to red to orange, and the skin is bitter enough that it is always removed.

LATIN NAME: Cyphomandra betacea

COMMON NAME: Tamarillo

Plant Profile

Tamarillo is a small, soft-wooded tree from the Andes, grown for fruit that looks like a large plum and tastes like a tomato crossed with a passionfruit. Cyphomandra betacea, now placed in Solanum by some authors, reaches 2-4 m with a single stem that branches after the first flowering, and carries large, heart-shaped leaves with a faintly musky smell.

It is fast, sometimes alarmingly so: seedlings can flower within a year and fruit by eighteen months, which is quick for a tree crop. The trade-off is a short productive life of five to eight years and a root system that is easily disturbed by transplanting.

Science & Biotechnology

The fruit is a source of anthocyanins in the red and purple types, principally delphinidin and cyanidin glycosides, together with high vitamin C and a substantial carotenoid fraction in the orange and yellow cultivars. The colour difference between cultivars is a single pathway switch, and it has been used as a teaching example of anthocyanin regulation in solanaceous fruit.

The genus has also been a minor subject in solanaceous phylogenetics, since its placement between Solanum and Cyphomandra has moved more than once. Practical research has concentrated on post-harvest handling, because tamarillo bruises easily and ripens unevenly, and on virus indexing, since the plant accumulates several viruses when propagated vegetatively.

Uses & Benefits

The fruit is eaten fresh with the skin removed, or stewed, made into chutney, sauces and jams. The skin and the seeds are bitter and are usually discarded, and the fruit is acidic enough that it works better cooked with sugar than eaten out of hand.

In the garden the plant is a fast foliage subject for a sheltered, frost-free spot, and it fruits well in a large container under glass. It is grown commercially in New Zealand, which built an export trade around a fruit that originated in the Andes and was introduced there in the nineteenth century.

Growing from Seed

Sow fresh seed, since viability drops quickly in storage. Sow 5 mm deep in a free-draining mix at 18-22°C; germination takes two to four weeks. The seed coat is hard and a twelve-hour soak before sowing improves uniformity.

Grow the seedlings on in bright light, cool rather than hot, at 15-20°C. Plant out after the last frost in a sheltered position with rich, well-drained soil, and stake the young tree because the stem is brittle and the fruit heavy. Protect from wind, which shreds the large leaves, and from frost, which kills the plant outright. Prune lightly after harvest to keep the canopy within reach.

Our Take

Tamarillo is worth growing where frost is not an issue, largely because nothing else fruits so quickly from seed. Do not expect a long-lived tree, and do not expect the fruit to taste like a tomato: it is sharper and more aromatic, and it is better cooked.

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