While forward healthy sugar beet does not routinely respond to additional foliar nutrients, there is a place for them in fast-growing or compromised crops.
That was the message from Simon Bowen at the BBRO鈥檚 recent BeetField grower days, where he noted the dry spring had created a massive growth stage spread between and within fields by late May.
鈥淐onsequently, crops need encouragement to grow away rapidly,鈥 he told growers.
鈥淏eyond nitrogen, phosphate is central to early root growth, which drives canopy development. We know most crops are on high P soils, but freshly-applied, freshly-available phosphate is easily accessible. Some growers have had success enhancing canopy growth with DAP applied with their top dressing, and that is backed by a trial we have conducted near Kings Lynn.鈥
Issues
In terms of what growers can do at this stage of the season, Mr Bowen highlighted the need to address suspected issues before the 12-16 leaf stage, and to not apply products in high temperatures or to wilted crops.
鈥淢any growers routinely apply manganese and magnesium, but often too late 鈥 visible deficiency symptoms mean crop growth has already been compromised. Late spring rain can see canopy sizes double in a week. Such crops need a prompt first Mg/Mn application to propel them rapidly to the 12-leaf stage by mid-June, given that they will then be running out of insecticide protection."
Nutrients
鈥淢anganese and magnesium are key for chlorophyll and chloroplast production, and a little-and-often application of 1-2kg/hectare at seven-14 day intervals works best.
鈥淎lso important in chlorophyll production, sulphur, typically deficient in sandy, low organic matter soils, can be addressed via manganese/magnesium products containing sulphate. And we have seen increasing numbers of plants with boron deficiency at BBRO鈥檚 plant clinic over recent years. Light land and dry conditions impact uptake, and early use can reduce loss of later-season leaf growth.鈥