How to get record yields

Want to shoot out the lights with your maize, sunflower or soya crop? African Farming spoke to Johan Meyer from Hartbeesfontein in North West, the winner of the Grow for Gold competition, to hear how this maize and sunflower farmer managed to achieve a record sunflower yield of 4.4t/ha.

“Everything starts with the soil – and one of the basics is to rotate your crops. Soil may also look all the same at first, but once you start digging below the surface, the differences become apparent.

I give my soil both biological and chemical treatments – chicken manure and lime, in averages of 1.7t/ha lime and 2t/ha chicken manure, applied in thirds (to each field every three years). This has resulted in healthy, fertile soil.

“The next step is to leave my crop residues on the fields after harvest. Crop residues return a lot of potassium to the soil. I did a sum – by removing my crop residues, it would cost me R350 to R500/ha, excluding fuel cost, to replace that lost potassium.

“Farmers know about the value of macro elements like nitrogen, phosphor and potassium when growing crops – but don’t forget micro-elements like boron and molibdenium. They really give your yield that extra boost.

“We apply these two micro-elements as foliar treatments because boron is taken up by a plant’s roots. You also need to spray at least three times during the season to ensure sufficient uptake for growth.

“Make sure you use the correct product that contains molibdenium and boron. Our product also contains seaweed, another biological source of micro-elements that keep plants healthy and strong.

The first foliar application is done when the crops are knee-high, then at hip-height and then about two weeks before the sunflowers make their first buds or two weeks before the maize reaches pluming. We apply two litres of MoB [molibdenium and boron] per hectare on both the maize and sunflower.

“Don’t just sit back once your crops have germinated. Keep feeding your plants right through the season. “I believe a strong start results in a strong finish, especially as the first six weeks of a plant’s life determines its yield.

We use a locally produced biological product that gives plants a strong root system and enough energy to get off to a good start. It also serves as protection against fungii and nematodes, because a healthy plant is much less prone to suffer from nematodes and plant pathogenic fungii. Speak to your local agronomist or chemical representative about these products.“

A programme that relies too heavily on chemical products also stunts yield. Even Roundup-resistant crops take at least two weeks to recover fully from a spray of pesticide.

In a season like the past one, where we had a lot of cloud cover and cooler days, another setback like recovering from a spray can have a significant effect on your plant’s ability to grow.

We are currently conducting a trial to see if a foliar treatment can help reduce the stress a plant is subjected to after a chemical treatment. We’ll have the results after this season’s harvest.

“Lastly, a foliar sample applied three times during the season – at knee-height, hip-height and two weeks before pluming – is extremely important. Also, don’t forget to have your soils tested regularly at the right laboratory to establish if your macro-elements are in balance, You might have a problem like a calcium imbalance.

“It’s the balance between all these different factors that will increase your yield. Once your soils are healthy and in balance, and you apply a strong combination of foliar treatments, you’ll see magic!

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