Maximising your crops’ potential with foliar nutrition

This has serious implications for crop growers. Chris Harrold, YaraVita Product Manager for the UK and Ireland, discusses the importance of analysis to ensure crops are getting sufficient nutrients, and how a complete crop nutrition programme can help maximise crops’ potential.

“Waterlogging alters the physical properties of the soil by reducing porosity, so you get that anaerobic situation which limits root growth,” says Chris. “It also has a negative impact on soil microbes and causes nutrient leaching, particularly of nitrogen, sulphur, and trace elements like boron.”

Analyse to stay on top of crop nutrition

Plant nutrients have specific and essential functions in crop metabolism, and a lack of any one of these nutrients limits growth. The most important thing growers can do to maximise crop yields is ensure nutrient sufficiency. This can be achieved by carrying out analysis throughout the season.

“Quite a lot of growers and agronomists are using tissue analysis, sap analysis, soil analysis, and grain analysis throughout the season to monitor how successful their crop nutrition programme is,” explains Chris. “Any one measure won’t give you the full picture, but a combination will really help you maximise what you can do with your crop nutrition. It’s all about getting the basics right.”

The best route growers can take to healthy, plentiful yields is a complete crop nutrition approach. Foliar nutrition is not a silver bullet when it comes to maximising yields, but it’s a common-sense addition to a crop nutrition programme.

Essential foliar nutrition for OSR

There are a range of nutrients which are essential for maximising oil seed rape yield and ensuring overall crop health. These include boron, manganese, and magnesium. Boron plays a key role in flowering and cell structure throughout the growing period, manganese aids photosynthesis, and magnesium is a key component of chlorophyll.

Deficiency of boron in the rapid stem extension stage results in splitting in the stems. As the nutrient is not particularly mobile in crops, early supplementation can help prevent the issue. This is also the case with manganese and magnesium.

“For oil seed rape, I would recommend applying YaraVita Brassitrel Pro at a rate of three litres per hectare at that rapid stem extension phase in the spring,” says Chris. “It’s specifically designed for oil seed rape and we’ve seen this rate of application consistently providing over a quarter of a ton to the hectare yield increase.”

As some oil seed rape crops have had a challenging year, growers may want to top up nitrogen applications later in the spring with a multinutrient product such as YaraVita Croplift Pro.

Ensuring nutrient sufficiency in winter cereals

Winter wheat yield is driven by the number of ears per square metre, the number of grains per ear, and the weight of the individual grains. The AHDB benchmark for an 11-tonne crop of winter wheat is 460 ears per square metre, 48 grains per year, and 50mg per grain.

“It’s critical that growers assess their crops and maximise biomass as much as possible over the next month. This means applying enough nitrogen and sulphur to improve the root structure and to encourage crops to tiller,” explains Chris. “Sulphur in particular should be applied little and often throughout the season as wet weather causes leaching through the soil. It’s not just about nitrogen and sulphur with winter wheat however, manganese is essential for building biomass and phosphate is important for root growth. Due to the waterlogging we’ve seen, a foliar application of phosphate can help crops whose roots have been compromised by waterlogging.

“Our recommendation to bypass the root issue is getting some fresh phosphate into the leaf with a foliar nutrient product like YaraVita Crop Boost,” says Chris. “It has a readily available form of phosphate in it as well as some potassium, magnesium, and zinc. It’s quickly taken up by the plant and provides a lasting feeding effect.”

Previous Yara trials have shown that crop boost applications followed up with an application of YaraVita Gramitrel have resulted in yield increases of over half a ton to the hectare.

“Growers should apply crop boost during the tillering period and follow this up later with an application of Gramitrel at growth stage 30/31. We’ve seen a good return on investment with the sequenced application of these products,” adds Chris.

Protecting pulse crops from nutrient deficiency

Pulse crops can be forgotten when it comes to foliar nutrition. However, given the recent excessive rainfall, crops like winter beans in the ground will have suffered. They rely on root nodules to supply the plant with nitrogen, and if the roots have been compromised, this can impact on growth. A foliar application of nutrients can help to overcome these issues.

“A complete foliar product will help top up the crop’s requirements for those key nutrients. For pulse crops, our recommendation would be to use YaraVita Photrel Pro,” says Chris. “It’s a fully soluble powder product combining a balanced combination of essential nutrients for legume crops. Apply 3 kilos per hectare when there’s enough leaf cover to intercept the spray and repeat later in the season when the crops are flowering and setting seeds.”