Innovation adds value. By Anna Mouton.
“M.9 has been used successfully as a rootstock all over the world,” says Keith Bradley, general manager of agri-services at Fruitways Farming, “but there was always the perception that M.9 wouldn’t work in South Africa. We’ve shown that M.9 can work.”
The Orchard of the Future at Graymead, Vyeboom, was established in 2011 with Royal Gala and Fuji on M.9 Nic29. The orchard was planted at 3.5 by 1.2 metres, and trees were trained to a spindle system. “At the time, our conventional orchard was typically planted at 4 by 1.5 metres,” recalls Bradley. “We’re planting closer now.”
Planting distances aren’t the only change inspired by the Orchards of the Future. Many other innovations — in areas as diverse as soil health and harvest management— have resulted from the programme.
In addition to the Royal Gala and Fuji on M.9 Nic29 in the Orchard of the Future, Bradley gathered data on the performance of Royal Gala planted on G.778 and MM.109 in the same year. He cautions that the G.778 was not planted at the ideal spacing. “It was planted at 4 by 1.75 metres — I would plant it at higher density — but I used it as a comparison because it’s on the same farm.”
The trees on M.9 Nic29 were defruited in the first leaf. Both Royal Gala and Fuji on M.9 Nic29 bore approximately 15 tonnes per hectare in their second leaf, and the Royal Gala went on to produce 25 tonnes per hectare in its third leaf. In contrast, Royal Gala on MM.109 bore a scant five tonnes in its third leaf, while Royal Gala on G.778 only yielded its first harvest in its fourth leaf.
Neither Fuji nor Royal Gala on M.9 Nic29 achieved a total cumulative yield of 300 tonnes by sixth leaf, but both beat Royal Gala on MM.109 by more than 100 tonnes. The Orchard of the Future broke even earlier than the conventional orchard.
“M.9, done properly, definitely brings you early cumulative tonnages and outperforms MM.109,” says Bradley. “But I don’t think M.9 necessarily ticks the box for long-term high-tonnage sustainability in the EGVV region.”
Annual production of 100 tonnes per hectare when in full production was another objective of the Orchard of the Future. The Royal Gala on M.9 Nic29 reached 104 tonnes once — in eighth leaf — but dropped to 72 tonnes the following year. None of the other orchards in the data set have so far attained 100 tonnes per hectare.
Data on fruit size and quality were only collected for the Royal Gala on M.9 Nic29. Both size and quality were good, and class 1 pack-outs were high. Over the course of the programme, less than 3% of the fruit fell in the local 2 and juice-quality categories.
According to Bradley, soil quality was less than ideal. “Due to a lack of soil depth, we had to ridge, which led us to decide on a 3.5 metre row width. Otherwise, we would possibly have planted more toward 3 metres.” There was a risk of increased soil temperatures in the ridges, and mulch applied on narrow ridges tends to be displaced.
The initial trellis was also too light. “These precocious rootstocks need to be supported or they fall over,” explains Bradley. The trellising system has cables instead of wiring along the top, as well as cross-wires and stronger anchoring. In spite of starting with poles that were closer together than usual, it was necessary to add more poles after the first year.
Bradley has a question mark over the true-to-typeness of the M.9 Nic29 rootstocks they received. “When we saw the growth habit, we pulled some trees out.” If he had to do a trial again, he says that he would choose different cultivars for the scions. “I would never plant Fuji on a trial site again — it’s the worst variety when you’re trying to get decent data.”
As for the Royal Gala, Bradley found that the Brookfield strain, relative to other Royal Gala strains, was very variable. “There was massive variation from tree to tree in the same orchard, and not only on the M.9 rootstock.”
In spite of all these challenges, Bradley believes that the trial demonstrated the ability of M.9 Nic29 planted at high-density to outperform conventional orchards. “It highlighted that the older Merton rootstocks are the past. They’re not consistent enough in getting cumulative tonnages and productivity, especially on replant soils in our area.”
Laying the groundwork
M.9 has a reputation for being sensitive to heat. The Orchard of the Future at Graymead incorporated mulch to maintain cooler and moister soils. “At that stage, mulch wasn’t widely implemented,” remembers Bradley. “It was considered possibly a luxury — it adds another dimension of cost.”
Wood chips were brought in and manually spread on the ridges. The mulch was extremely effective, but the transport and labour made it expensive. “The other problem is getting hold of it in large volumes. If everybody mulched, there wouldn’t be enough to go round,” says Bradley.
Nonetheless, the benefits of covering the soil with organic material are substantial. Bradley has been working with growers to explore the use of cover crops. Cover crops are the equivalent to growing your own mulch, and have no transport costs.
“You have to farm with nature,” says Bradley. “You have to continuously diversify on your orchard floor to bring sustainability. It’s not sustainable to rely only on continuous application of herbicides and inorganic fertilisers, without looking after soil health.”
Bradley sees improved soil health as a cornerstone of future orchards, especially in the Elgin-Grabouw-Vyeboom-Villiersdorp area, where the majority of orchards are established on replant sites, and replant disease is rampant. Although he agrees that precocious rootstocks and high-density plantings are the way forward, he isn’t so sure that M.9 is the best option for his region.
“It’s my perception that M.9 does better in the higher chilling areas,” says Bradley. He is interested in the rootstocks coming from the Cornell-Geneva breeding programme, not least because of that programme’s focus on replant resistance and woolly apple aphid tolerance. “I think that will help on these replant sites. But you can’t sit back and think, Geneva will carry me through. We need to change the environment in which we farm, by improving soil health.”
The Orchard of the Future at Graymead has done more than change thinking around rootstocks and densities. “When it comes to efficiency, the Orchard of the Future has brought a whole lot of things that we now use in our standard orchards,” says Bradley.
One of these is better water management. “We knew M.9 was a shallow rootstock, so we looked at getting our irrigation scheduling and the quantity right,” says Bradley. Greater focus on irrigation efficiency has become a common thread throughout their company as well as in the wider industry.
The potential for improved spray efficiency was another lesson learnt. “As soon as we took our standard spray cars into these high-density orchards, it really highlighted how wasteful the spraying was,” explains Bradley. The traditional axial-fan sprayer and habitual high-volume applications were clearly inefficient and polluting. Subsequently, the approach to spraying all their orchards, including those with 4-metre rows, has been adjusted.
Even harvesting methods benefitted from the Orchard of the Future. Narrower rows are a little too cramped for bin-trailers, so it makes sense to put the bins on the ground in the orchard. This creates an opportunity to limit the number of people picking into each bin, thereby making it easier to reward those who take care — and to hold others accountable for fruit damage. Bradley says that they now harvest all orchards on flatter terrains with the bins on the ground.
“When you plant an Orchard of the Future, it’s to the best of your knowledge at the time,” says Bradley. “You need to be adaptable because the plan won’t be perfect. But at the end of the day, you’re sowing the seed of technology and innovation.”
The biggest benefit, in his view, is that it gives growers the opportunity to see new ideas in practice. Whereas it’s important for technically-minded people to go overseas and see the latest developments, there need to be local trials. “Because it’s never a copy and paste,” emphasises Bradley. “You need to think about the environmental differences, and try to adapt the idea, and then put something in the ground for growers to look at.
“I’m absolutely sold on the Orchard of the Future project. There’s nothing better than getting growers together physically in an orchard. The talk becomes about more than just what they’re seeing.”
Image: Keith Bradley — left — and Douw Vermeulen, area manager at Fruitways Farming
Supplied by Anna Mouton.
Table 1 The Graymead Orchard of the Future at a glance
|Royal Gala Brookfield and Fuji Kiku
|3.5 x 1.2 metres
|Trees per hectare
The past and present orchard team
Louis du Plessis
Johan van As
Tobie van Rooyen