Orchard spraying by drone

Which orchards the drone is for

Orchards of 10 ha or more we take anywhere in Serbia; smaller areas only within 20 km of Opovo. Our agronomist Nikola adapts the flight to different fruit species and training systems, so the same terms apply to plum, apple, walnut and other orchards.

A big advantage of the drone is working after rain: only the road to the orchard needs to dry, and if you have a tarmac access road, we can spray the same day.

How the drone sprays the canopy

Our DJI Agras T70P sprays orchards from the air, flying directly above the row of trees and atomising the product into droplets of 50 to 500 microns (DJI figure). The strong downdraught from the rotors pushes the droplets deep down through the whole canopy. From monitoring small pests in practice, we can see that the airflow carries the product to every part of the plant, including the sensitive underside of the leaf. How deep it penetrates depends on the fruit species, the density of the foliage and the training system.

The drone has dedicated software for orchards (the "hill and orchard" terrain mode and the "fruit tree" mode). The orchard is scanned first, and the drone then builds a precise 3D flight map that takes the layout and height of the trees into account (DJI Agras T70P user manual).

Because of the large leaf mass, an orchard always needs more water than a field. Field crops use 15 to 20 litres per hectare; an orchard uses much more, depending on the treatment. More water means more landings and more flights, which the standard €10 per hectare surcharge covers. You supply the water and the product at the orchard. Nikola mixes the solution and always informs local beekeepers before flights with insecticides, which is critical when the fruit trees are in blossom.

When to spray an orchard: timings by stage

Your agronomist always draws up the protection plan and spray programme, based on the fruit species, the variety and disease pressure.

• Winter spray: done after pruning, usually by the end of February or early March. It reduces the pests and diseases that overwinter in the canopy and on the bark. It is applied only above 8 °C and in calm weather, because mineral oils lose their ability to stick in the cold (Agro Info Net).
• Bud swell: the key moment for the first copper treatment (especially on plums), to control pathogens that overwinter on the tree, such as the cause of blossom blight and brown rot (Monilinia).
• Flowering and after flowering: treatments against Monilinia, both in flower and at petal fall.
• Summer and autumn: treatments during fruit growth and colouring, plus the autumn copper spray ("blue spray") once most of the leaves have fallen, an important part of stone fruit protection (Sadnja, plum protection programme).

We usually do foliar feeding in orchards before and after flowering: see foliar feeding by drone for details. The exact treatment dates are set by warnings from the Plant Protection Forecasting and Reporting Service (PIS) and by your agronomist, who chooses the product and the rate.

What orchard spraying by drone costs

Orchard spraying by drone costs €25 per hectare up to 20 ha, €22 for 20 to 100 ha and €20 above 100 ha, plus the €10 per hectare surcharge for permanent crops. Foliar feeding costs the same. You supply the product and the water at the orchard. Travel within 50 km of Opovo is free; beyond that we charge €1 per extra kilometre, one way.

Example (a new client's first order): 12 ha near Vršac, 91 km from Opovo.

Orchards need many treatments a season, so packages make a real difference: a package of 5 or more treatments gets 10% off. For the same 12 ha near Vršac, five treatments in a package cost €2,063.50 in total (an average of €412.70 per treatment, including travel and the free hectare on the first treatment). You pay after each treatment, and clients with a package get priority when booking. Rules and worked examples for treatment packages are in the price list.