—story by Kate Prengaman
—photos by TJ Mullinax and Kate Prengaman

Greg Lang, left, the International Fruit Tree Association education director, and Oewerzicht Farm manager Gordon Anderson talk about the South African farm’s PremP009 pear trial, including this multileader system and interstem plantings — since the cultivar, marketed as PIQA Red, is incompatible with quince rootstocks. The Two-A-Day Group, of which Oewerzicht is a member, coordinates its own research projects, and farms bid on the rights to host trials and share the findings across the 61-member cooperative. (TJ Mullinax/Good Fruit Grower)
Greg Lang, left, the International Fruit Tree Association education director, and Oewerzicht Farm manager Gordon Anderson talk about the South African farm’s PremP009 pear trial, including this multileader system and interstem plantings — since the cultivar, marketed as PIQA Red, is incompatible with quince rootstocks. The Two-A-Day Group, of which Oewerzicht is a member, coordinates its own research projects, and farms bid on the rights to host trials and share the findings across the 61-member cooperative. (TJ Mullinax/Good Fruit Grower)

If there’s one thing International Fruit Tree Association members have learned in their visits to growers around the globe, it’s that tree performance and the required farming practices vary widely, depending on the climate. 

So, it’s no surprise that South African growers have deployed their own trial plantings to modernize their apple orchards with dwarfing, precocious rootstocks and find the new apple and pear cultivars best suited to their climate. The IFTA tour of the Western Cape in December included visits to trials planted by individual growers, cooperatives and industry service providers. 

At Oewerzicht Farm, in Greyton, one such trial included a new pear, the European and Asian pear cross PremP009, marketed as PIQA Red, trained in a variety of systems. One in particular, a planar, multileader approach, looked more like UFO cherries than any pear in North America. 

Many of South Africa’s newer pear orchards grow in high-density systems on dwarfing quince rootstocks. However, PremP009, while an intriguing cultivar, is incompatible with quince, said Gordon Anderson, Oewerzicht’s orchard manager. Instead, the orchard hosts experiments with interstem plantings and multi-
leader systems on more vigorous rootstocks.

“This is a horticulturist’s playground,” said Graeme Krige, the general manager for Fruitmax Agri, who works as an advisor to Oewerzicht and its packer, the Two-A-Day Group. 

It’s also a collective effort.

The Two-A-Day Group is owned by 61 growers, with the average shareholder farming 50 hectares. Those growers can’t individually afford to take a risk on a new variety or new training system, Krige said. Instead, the Two-A-Day board approves an annual budget for “project orchards” and outlines their experimental priorities. Under this model, the company subsidizes establishment costs, and interested growers apply for the rights to host the trials. 

In addition to the new pear, Oewerzicht hosts trials of Inored, a new apple from the French breeding program INRAE, which is marketed as Story. The trial includes multiple rootstocks on spindle and bi-axis systems. 

“It’s a scab-resistant red, which is very interesting to us, but we still need to understand its production,” Krige said. They have replicated the trial in several Two-A-Day production areas to see how the new cultivar performs in each microclimate. 

An early Granny Smith strain discovered in South Africa, Louterwater Granny Smith, was planted at the same site in a similar trial design. In that trial, the Two-A-Day Group is collaborating with Hortgro, the pome and stone fruit industry association that funds research through grower assessments, and Provar, an independent evaluation company that serves the South African deciduous tree fruit industry. 

Tristan Dorfling, the pome rootstock program manager for Provar, explained that, among other things, the trial aims to examine the influence of rootstocks on bud breaking. Granny Smith is very prone to blind wood, which is exacerbated by the lack of winter chill accumulation in South Africa. 

Rootstock performance in one climate doesn’t necessarily translate to another, so South African growers have found they need to conduct their own extensive trials to understand what newer rootstocks might have to offer their production systems. Geneva 757, a dwarfing option drawing some interest, grows at Oewerzicht Farm, in Greyton, as part of a series of trials managed by Provar, an independent evaluation company that serves the South African tree fruit industry. (TJ Mullinax/Good Fruit Grower)
Rootstock performance in one climate doesn’t necessarily translate to another, so South African growers have found they need to conduct their own extensive trials to understand what newer rootstocks might have to offer their production systems. Geneva 757, a dwarfing option drawing some interest, grows at Oewerzicht Farm, in Greyton, as part of a series of trials managed by Provar, an independent evaluation company that serves the South African tree fruit industry. (TJ Mullinax/Good Fruit Grower)

At just 14 months since planting, the trial block was expected to harvest 25 tons per hectare on average, though estimates varied by rootstock.

“It’s unusual to crop in the second leaf, but the Genevas’ precocity is quite evident compared to M.7 and M.9,” Dorfling said. 

Dorfling also showed the IFTA group older rootstock trial blocks at Oewerzicht that sought to compare the vigor, yield, yield efficiency and fruit quality of vigorous, semidwarfing and dwarfing rootstocks. That trial is part of a larger project supported by Hortgro and the rootstock licensees. In the 2018 and 2019 plantings, both with cultivar BigBucks Gala, G.757 stood out in terms of efficient production for the size of the tree. 

“M.9s can struggle to fill space, but G.757 fills space very well, so you get more production more quickly for the same space,” Dorfling said. 

Oewerzicht also conducts its own experiments around labor efficiencies, said orchard manager Gordon Anderson. He likes V-trellis systems that allow his workers to ride platforms for pruning, training and thinning work. 

“The platform is moving the whole time, and they have to keep up,” he said. 

His current V-trellis systems still have too many lower branches, so he wants to move from two leaders to four, further reducing vigor to allow for formally trained systems. 

Formal training may be the way of the future at Dutoit Agri as well. Technical manager Willie Kotze showed the IFTA his “experiment orchards” block, which included trials of several Geneva rootstocks and newer cultivars, including WA 38, the apple marketed as Cosmic Crisp. 

At Dutoit Agri, dwarfing Geneva rootstocks are under evaluation as part of an “experiment orchards” trial block, said Willie Kotze, Dutoit’s technical manager. (Kate Prengaman/Good Fruit Grower)
At Dutoit Agri, dwarfing Geneva rootstocks are under evaluation as part of an “experiment orchards” trial block, said Willie Kotze, Dutoit’s technical manager. (Kate Prengaman/Good Fruit Grower)

“Between the mountain slopes where we farm, it’s more difficult to go to dwarfing rootstocks,” even compared to other regions in South Africa, Kotze said. “I have seen M.9s in Europe be more vigorous that M.7s in our climate.”

In his trials, Geneva 969, for example, was clearly struggling due to virus issues in the scion material. Another experimental block, planted on M.9 and formally trained onto a seven-wire trellis, was showing promise, however. 

“The idea is to use less labor once we set it up,” Kotze said. The formal training reduces the vigor, the trees need fewer inputs, and it’s easier to teach their workers how to prune and thin the trees. A recent summer pruning pass had just been done to get more light into the canopy and encourage spur development. 

“The uniform quality is what we want from this,” he said. •