Ardent management and continuous testing and tweaking of farming practices has kept Curlews Farm at the top of their game. Sarel Venter, Curlews’ farm manager, explains what it takes to produce an award-winning crop.
Delivering an impressive 1.94% unsound kernel recovery (USKR), Curlews was lauded for having one of the most improved USKs within its category at the annual Green Farms Nut Company farmer awards.
The farm in Mpumalanga follows a strict programme for managing all aspects of tree health and nut production to ensure a good yield and exceptional quality.
Curlews Farm has four different varieties: Nelmac 2, Beaumont, Integs and Nelmac 26. Any expansion or replacement of trees is done with the former two varieties. Venter explains that these two give a good mix between big nuts and high yield from the Nelmac 2, while the Beaumont is a hardier nut that can better withstand insect damage and hail. “The husk is also harder so it doesn’t burst open before the nuts are ready, as is often the case with Nelmac 2. We believe in spreading our risk across the cultivars because then we win from both sides.”
The orchards vary in age from 3 – 20 years, delivering a yield of between 4 tons and 9 tons per hectare. The latter is achieved on the older Nelmac 26 blocks.
Optimising the orchard
Due to the varied age group of trees, management requires a firm hand and a well-structured and executed plan. Venter states that the farm makes use of technical advisors and consultants to work out fertiliser and crop protection plans for every stage of the annual cycle.
Post-harvest, pruning commences with a specific focus on creating opportunity for light and chemical spray penetration in the trees. This is followed by preventative crop protection applications. Venter says that thrips, especially, is a problem on the farm. Since the pest attacks the leaves, it has a drastic effect on yield if not brought under control.
For this reason specific products are applied as early as August to control the thrips. Thrips control during the whole year is of utmost importance.
Emphasising the value of continuous checks and balances, Venter notes that the pH of the water needs to be correct to ensure maximum efficacy of all the chemicals used during the season. With all of the spray applications on the farm an adjuvant is added to ensure proper wetting and spreading of the chemicals on to the leaves.
Venter says that a good yield is dependent on the tree having enough energy to produce a good crop. This necessitates the right mix of fertiliser at the right application rate to give the tree sufficient energy to produce nuts and keep them through the November nut drop period.
Thobi Nel, Curlews’ consultant from Nulandis, explains that they focus on getting the soil right so there is a healthy tree with healthy leaves that can provide a good crop. “A healthy tree is more resistant to pests and can carry a bigger volume of nuts. It is therefore important to maintain a balance between what you do below and above the soil.”
Nel says that a healthy tree is created through a good root system with robust hair roots that can absorb all the nutrients and result in good flowering and nut set. “Root stimulant products will aid in hair root development. During certain times of the year you need specific micro and macro elements.
“Once tree health is achieved you have to balance it with crop protection to take care of the nuts that have formed through effective and responsible use of chemicals.”
Guarding the nuts
Once the nuts are in place a crop protection programme must be initiated to control problems like stinkbug, husk rot, macadamia nut borer and false coddling moth. Nel says it is crucial that these chemicals are only applied when bees are not active in the orchard. “The trees must be completely dry before the bees arrive or they will be harmed.”
Venter relates a lesson learnt on the farm through trial and error. “It’s important not to over spray because if you are drenching the soil below the trees with the chemicals, from applying too much you end up killing many of the beneficial organisms living in the soil that we also work hard to keep healthy through organic fertilisers.”
The spraying equipment is calibrated regularly and tests done in the orchard to ensure the applications are reaching all the branches. Venter says this is an important aspect of management, otherwise “you are wasting money on chemicals and not getting any results”.
He notes that due to strict withdrawal periods, harsher chemicals are applied earlier in the season and lighter products with shorter withdrawal times closer to harvest.
Discussing Curlew’s low USKR, Venter says in addition to following a strict crop protection programme, scouting is crucial to reduce damage to the nuts. “You must walk through your orchard regularly and if you see there is a pest you must be able to treat the orchard as quickly as possible. Seven days after we have sprayed we scout by laying down ground sheets around ten trees per block. We then spray those trees with pesticides and monitor what falls on to the sheets. If there are still too many bugs on the ground you know you need to spray again.”
The final stretch
Before harvesting begins, the orchard floor is cleaned to remove any sticks, stones or weeds to ease the nut-collecting process. Ethapon is sprayed on the Beaumonts to release the nuts while the other tree varieties are knocked. Venter says it is important to apply the correct quantity of Ethapon as overdosing will result in the leaves dropping, damaging the trees.
The nuts are sorted before being sent to the processor. “We take out our unsounds on the farm and we separate our nuts into two batches – those more than 18mm in diameter and those under. Next season we will also start sorting nuts that are 20mm and over. The sorting process is the final step in ensuring a good crop is delivered to the factory, and should not be neglected.”
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