Rewriting the rules on apple rootstock longevity

The use of Geneva rootstock CG 778, in combination with regenerative farming techniques to ensure healthy soil, has the potential to revolutionise apple production in South Africa, according to Elgin grower Ian Cunningham. He spoke to Glenneis Kriel about his techniques.

- Glenneis Kriel

FAST FACTS

The use of a new apple replant disease-resistant rootstock may allow farmers to graft trees for up to 60 years.

Healthy soil with high organic matter content lengthens the viability of rootstocks.

Regenerative farming techniques, such as the use of cover crops and compost, play a crucial role in improving soil health.

Rootstocks, like crops of every type, are under constant improvement, and the arrival of a significantly better variety is bound to arouse interest. Western Cape apple producer Ian Cunningham is convinced that Geneva rootstock CG 778 is such a variety, and when combined with healthy soil, can increase rootstock longevity by a huge margin, saving farmers millions of rands.

CG 778 is also tolerant of apple replant disease, unlike most of the rootstocks used in South Africa. This on its own makes it a potential game changer.

FIRST-HAND OBSERVATION

Cunningham, who grows apples on his family farm, Fine Farms, near Elgin, became convinced of the value of CG 778 after visiting the Cornell Geneva apple rootstock breeding programme in New York State and growers in Washington State in the US. Back home, he persuaded local apple nurseries to get their hands on enough tissue culture of the variety to use on 10ha of his orchards in his 2020 apple planting programme.

The CG 778 rootstock is vigorous yet precocious, so should work well in Cunningham’s slender spindle system orchards.

“The CG 778 rootstock got me thinking that we might be able to move away from replanting trees every 20 years or so, to a situation where we can merely graft new plant material onto the old rootstocks,” he says.