Nitrogen supplementation in potatoes

The growing season has started turbulently. Due to the warm weather and a good moisture supply, the potato leaves develop quickly. This foliage growth has put a lot of strain on the nitrogen stocks in the soil. To support the further growth of the potatoes, the growers have already started adding fertilizer to their potatoes.

Nowadays there are various options for determining the amount of additional fertilizer. Ranging from the time-honoured 'farmer feeling method' to flying a drone; to automatically generate additional fertilization advice from there.

Fertilize crop tour
Agrifirm is a partner of the Crop Tour† Together with Agrifirm advisors, 2 of the plots (Fijnaart en Middenmeer) was selected to use modern techniques to determine what the correct nitrogen application advice is (from a location-specific point of view). This is to guide these potatoes to the desired optimum yield.

In consultation with the growers of these plots, the assignment was given to the collective Drone workers to scan the fields with an 'Ebee drone', which provides high-quality, high-resolution maps (many pixels per square meter). The drone has consequences for the plots on 20 June (Fijnaart) and 23 June (Middenmeer). The footage was processed by Droneworkers and delivered to Agrifirm for agricultural interpretation.

To arrive at a task map with variable nitrogen advice, Agrifirm used the NBS app on the geoplatform www.akkerweb.nl† Important input is data such as planting date, variety and target yield. For the parcels participating in the Crop Tour, most of these data were of course already known.

A target yield of 63 tons has been chosen on the Fijnaart plot. This resulted in an average donation of 400 kilograms of NK 16-0-30, with a spread of 300 to 600 kilograms. A target yield of 60 tons has been assumed for the Middenmeer plot. Here, 27% is spread with CAN and the variation in the product to be spread is 210 to 411 kilograms. This gift is capped at 411 kilograms, because (due to flooding and different soil cultivation) a big difference has arisen in growth.

(Text continues below the image)Agrifirm conducted research on the Fijnaart and Middenmeer plots.

Execution of the task cards
The plot in Fijnaart was fertilized this week (week 27). For this grower it is the first time that he will fertilize his potatoes on the basis of a variable application task card. The grower in Middenmeer has no option for variable spreading and will therefore apply additional fertilization in the standard way. Nevertheless, the nitrogen advice card does give him insight into the differences within the plot!