Planting has got under way in earnest across the northern parts of England over the last couple of weeks. Conditions are generally quite good, although there are some parts of fields that are a little too wet and I am urging my growers to lift out over these areas, I don’t want them creating a problem later on when it comes to harvest.
Herbicides have been applied to chitted crops in Cheshire, which have now started to emerge, albeit very slowly now we are in to a northerly air flow again. Timing of herbicide application is crucial, particularly if soil temperatures remain cool and emergence is delayed, you don’t want to knock the crop once it has emerged. It is worth remembering that residuals such as prosulfocarb and pendimethalin are not that soluble, certainly when compared with metribuzin, so if possible apply when ridges are moist for best effect.
The news that some Vydate (oxamyl) has made it to distributors has been generally welcomed, although by the time this was announced most growers had made contingency plans with field/variety selection and the use of alternative products. I understand that Vydate will be fully available again for the 2017 crop.
Don’t forget that as planted crops start to emerge, potato dumps will start to grow as well. These need to be well managed to reduce the risk of early late blight outbreaks, particularly bearing in mind the mild winter. The best option is to cover heaps with black plastic to stop growth, failing that then chemical control of sprout growth is the alternative.
One approved option is to kill new haulm growth using glyphosate. However, Reglone (diquat) can be used to treat haulm on outgrade piles using a knapsack sprayer under an Extension of Authorisation for Minor Use (EAMU) arranged by AHDB Potatoes and Scotland’s Rural College. Two applications are approved with a maximum individual dose of 0.4ml of product/sq m (same as 4 litres/ha). Water volumes between 200 and 400litres/ha are acceptable, but the outgrade pile must be on a permeable surface. Growers who use Reglone for this purpose must have a copy of the EAMU authorisation (No. 20111882) from https://secure.pesticides.gov.uk/offlabels/