The tamarillo is one of those plants that have found its way to NZ without much fuss or fanfare. Originally known as the tree tomato, it was first listed in the nursery catalogue of D. Hayes & Sons back in 1891, almost 100 years ago.
The first small, commercial plantings appeared in the Mangere district near Auckland with the earliest plantings being the yellow varieties. Later, the red form appeared, and over the years has proved the most popular.
Most likely introduced from India, where the fruit is well-known, the tamarillo is actually native to the Andean region of South America. It can be found from Venezuela to as far south as Argentina and is a typical fruit of the Andean highlands.
Serious commercial growing of the tamarillo started before the Second World War, and scarcity of imported winter fruits during the war years provided an impetus in demand for the tamarillo in NZ.
The attractive prices received by tamarillo growers encouraged increased plantings and availability of fruits on the market. Since then, the tamarillo has become well established in the fruit shops and obviously enjoyed by New Zealanders. During the early sixties, when tamarillos were being exported to Australia and Canada, the name Tree Tomato was seen as unsuitable for promotional purposes. 'Tamarillo' was coined in 1967 and is now internationally accepted - even in South America where the fruit was formerly known as 'Tomate de arbol'.
The tamarillo is usually propagated from seed. Growers who grow their own plants select seed from their best fruiting trees, a practice which has resulted in the development of larger, more superior fruits. In fact, fruit selections in NZ are the best in the world. The tamarillo type grown in its native South America is actually small and often of poor quality.
The tamarillo needs little description in NZ. Sown from seed, it will rapidly grow into an attractive, shrub-like bushy tree with large, green, pungent-smelling leaves. The plant will start flowering in its second growing season, and the sweet scent of its flowers alone makes it worth having in the garden.
Flowering takes place over an extended period of time from late spring until as late as the month of May, with fruit developing soon after flowering. As the green fruits approach maturity, they turn dull purple in colour then a bright, shiny red at full maturity, with fruits maturing in succession from late March until October.
In the home garden, the tamarillo requires a nearly frost-free climate and free-draining soils high in organic matter.
The most proven export variety of red tamarillo is 'Oratia Round', a selection made in the Oratia district about 20 years ago. Other selections have appeared since, and modern tissue culture propagation methods are used to multiply trees of a uniform type.
One of the most interesting new tamarillos to have appeared in recent years is a pure yellow form, an entirely freak tree which lacks the red pigments which make up the red fruit. Instead, the fruits are yellow - as yellow as a lemon.
By sheer coincidence, I encountered a similar type of tamarillo growing in Ecuador, but these trees were evolved from the yellow tamarillo; a yellow tamarillo still has a lot of red pigment in its leaves and fruit. So now we have a yellow tamarillo which tastes like a red one, and a very similar tamarillo which tastes like an orange-yellow fruit. The Ecuadorean fruit is locally known as 'Oro del Inca'.
Another recent introduction from Ecuador is a normal yellow strain known as 'Columbia round', the fruits of which are of course, round. The tree itself is dwarfed, making it more resistant to wind, and harvesting is more efficient.
From Argentina, we have a very good red-fruited form which is very sweet, and in my opinion much better than the regular red, or the yellow for that matter. While the fruits are not as large as on some of our NZ selections, its good flavour makes this strain outstanding.
The tamarillo is botanically known as Cyphomandra betaceae (Sendt) and belongs to the Solanaceae family, the same genus to which the potato, tomato, tobacco and peppers belong. All the Cyphomandra species originate in the neotropics, and to this day most of them are little known. The only reference to many of the species may be found in botanical literature. In South America, nearly all of these plants can only be found growing in the wild.
During some of my plant exploring trips in the Andes, I have encountered two species, both of which received a botanical description only in very recent times.
The Casana (Cyphomandra casana) was totally unknown when I encountered it growing in the mist forest of the Andes at 2,500 metres. Seeds of the Casana were introduced here in 1977. The name 'Casana' we coined ourselves for lack of an existing name.
The Casana grows well in NZ, preferring a cool, moist climate and semi-shade, and is intolerant of both heat and frosts. It seems best-suited to areas like Taranaki, Nelson, and the West Coast, in areas where little or no frosts occur. The tree of the Casana is very similar to the tamarillo, with leaves of a dull green and tomentose (furry). The flowers are lilac. The fruit is also similar in shape to the tamarillo but is dull yellow, somewhat smaller, but more numerous on the tree. The flavour, though, is very unlike the tamarillo. It could be described as reminiscent of the scent of peach and passionfruit. The fruit is rather soft and quality is variable, although selection and breeding of this wild plant may result in a very interesting new commercial fruit.
In Ecuador the Casana has now become endangered, as much of its forest habitat is being destroyed by fire.
The Chambala (Cyphomandra sp. - probably in the hartweggii tribe) is another plant very new to the developed world. In fact, I think this is the first time details of it have ever been published. Travelling in Ecuador during 1988, the Chambala was discovered growing near the roadside in recently cleared jungle. As new roads are pushed through the last remaining forest, new plant species still come to light. How many species useful to man are being destroyed is impossible to tell.
Only three years before I visited this area, the only access was on horseback. In contrast to the Casana, the Chambala grows at much lower altitudes where near-tropical conditions occur. It's named after the district in which it was found, a broad valley of the Guayllalamba river on the Western slopes of the Andes. The tree itself is tamarillo-like, but much taller, with some trees growing as high as 5m. The fruits hang on what seem like strings, or long pendulous racemes. The size of an egg and pointed at one end, the fruits are green in colour, turning to yellow at maturity.
The only fruit I tasted was not ripe, so I couldn't get a good idea of flavour, but the first New Zealand fruits of the Chambala are ripening at Oratia at the moment, and hopefully will survive the prolonged rains of August. A few seeds were introduced in NZ in 1988.
During our warmer months the Chambala grows well. It survived the first winter and during the second growing season blossomed and set fruit (growing outside) . This winter, the trees were rather set back by adverse climatic conditions. The fruits are hanging on though, so I hope for the best. Obviously the Chambala is going to be more tender than the tamarillo, but it's a plant with some potential.
The Colombian Mountain Tomato (Cyphomandra hartwegii) is one of the few Cyphomandra species that is known in the country of origin, and is grown mostly in gardens and backyards. Botanically, it is allied to the Chambala, although it is an entirely different plant. It grows in Colombia at the same altitude levels as tamarillo.
The Colombian Mountain Tomato is a robust shrub growing as tall as 4m. In its juvenile stage, the large leaves are lobed, then, as the flowering stage is reached, the leaves become cordate and very similar to those of the tamarillo. The flowers are greenish in colour and very numerous. The fruit sets over a short period of time and is rather bitter, becoming edible only at full maturity. In Columbia, they're made into jams and jellies. We have some trees growing on Great Barrier Island which are producing a lot of fruit. The tree is very ornamental when young and well worth growing for that reason alone.
There are other Cyphomandra species growing in New Zealand too. Cyphomandra meridensis is a rather small shrubby plant with small blue flowers. The fruit are rather like Casana but smaller and the tree does not thrive here.
Cyphomandra fragrans. A small, rather woody shrub with marble-sized fruit, is useful only as an ornamental, although it might be used as rootstock for tamarillo.
Cyphomandra corymbiflora. Ornamental only. Cyphomandra costaricensis is very similar to the tamarillo, and is said to be a wild form. It may be used as a rootstock for tamarillo to overcome nematode problems.
There may be still others in this country, but I haven't seen them. What is certain is that there are still many more named Cyphomandras in South America, and perhaps more unnamed ones as well. Many of them possibly at risk as their native habitat is destroyed. Further exploration may well yield some outstanding possibilities for the future.
DATE: July 1992
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