Tamarillos and Passionfruit

The loss of Hort 16A Gold kiwifruit to the disease Psa has provided an opportunity for orchardist and pack house owner Geoff Oliver to diversify into other subtropical crops – passionfruit and tamarillos. He has cut out 2.3ha of Gold canopy, leaving the Bruno rootstock stumps down at ground level and planted 2200 passionfruit plants on new v-shaped trellis as well as 500 tamarillo plants. The kiwifruit rootstock has been left to grow again, as it appears to tolerate Psa, and new green and gold varieties will be grafted on when they become available. Thus the passionfruit and the tamarillos are short-term crop diversifications, which several people around the Bay of Plenty are also planting.

Geoff Oliver has a 14ha property in Oak Rd, Rangiuru, with about 10ha of kiwifruit pergola development. Over 60% is planted to Hayward Green, however 2.3ha of Hort 16A Gold kiwifruit which was only grafted on two years ago has succumbed to Psa disease. Last June it showed signs of the disease and by August, Geoff made the decision to take the full canopy out, cutting back the Bruno rootstock stumps to ground level. It was feared that all the roots would need extraction, which would also wreck the pergola structure, but Bruno has shown to be tolerant to Psa at present. The kiwifruit stumps will be left to sprout canes again, which then have to be regularly trimmed, but that will keep the roots alive. Geoff hopes he will be able to graft Psa-resistant varieties like G3 Gold and G14 Green on to the Bruno canes this coming winter. That will depend on the availability of these new varieties and the costs of plant variety rights. If the grafting to new varieties is carried out, commercial fruiting quantities will be a further two years away. In the meantime he has planted short-term crops to use the land and the structure – passionfruit and tamarillos.

Kiwifruit orchards are laid out in “bays” which are 5m by 3.5m, and in Geoff’s case he still has two Bruno kiwifruit plants growing within each of those bays.

Last November he planted two passionfruit plants per bay in the majority of the 2.3ha block, and three tamarillo plants per bay in the remainder.

The passion fruit need extra structural assistance, being V-shaped trellis and wires under the existing kiwifruit pergola. The tamarillos are self-supporting up to the pergola height of 1.8m, when Geoff hopes their branches can be trained into a T-shape, so that the fruit will hang down like kiwifruit.

The Oak Rd orchard is reasonably high and frost is not expected in the old kiwifruit blocks.

Both the passionfruit and tamarillos will not be producing commercial fruit until 2013, when Geoff hopes to send the bulk of the fruit for export.

Being small crops in the New Zealand context, both can be quickly over-produced, which would reduce prices for all growers, but he hopes the quantities planted and the export focus will avoid that happening.

Integrated plantings of subtropicals are not popular in the Bay of Plenty, but three other growers within the Kiwi Produce group have planted some passionfruit in former Gold kiwifruit blocks.

Kiwi Produce already packs and arranges domestic and export sales for tamarillos and passionfruit on behalf of other growers, as well as a vast range of other fruit and vegetables.

Both passionfruit and tamarillos have specific virulent pests, which require careful monitoring and spraying when the pests are detected.

Geoff and his staff members have sprayed regularly to control the tomato-potato psyllid (TPP) which carries liberibacter, which has been killing tamarillos in NZ since it arrived from the US about four years ago. Fortunately, TPP pressure has not been as great this summer as in the two previous summers and most young trees have established successfully.