Rice paddies and drones — when to spray and what to watch out for

Rice paddies are work where drones have a clear advantage, because fields are often flooded, hard to walk in and large.

Advantages in rice paddies

No trampling on rice plants, so there is no damage from walking.
It works even when the field is flooded, conditions in which traditional sprayers struggle.
It is fast in large fields.

Growth stages and spraying

Rice goes through several stages, from seedling, tillering and booting to heading and harvest. Each stage has a different sensitivity and different pests.

The stage that needs special care is flowering, because droplets and downwash may affect pollination. Discuss whether spraying at that stage is really necessary, and if it is, choose a suitable time of day.

Flight height above the rice canopy

Rice keeps growing throughout the season, so the height set at the start of the season will not work all the way through. Adjust it to the real height of the rice plants. Drones with terrain-following radar help keep the distance above the canopy, but you still need to check that it works correctly with a crop of that height.

Talk to your neighbours

Rice paddies are often joined together in large blocks with many owners. Spraying herbicide in one field can affect neighbouring fields if droplets drift. Telling neighbours in advance and leaving a buffer strip help reduce disputes.

Aquatic animals and bees

Many rice paddies also raise fish or are near natural water sources. Some substances are highly toxic to aquatic animals. Check the information on the label and keep the required distance from water sources.

If bees are kept in the area, tell the beekeepers in advance and avoid spraying while the bees are out foraging.

Keeping records

Record what was sprayed, when, in which field, and the rice growth stage at the time. This information is very valuable when you need to work out why this year's yield differs from last year's.
Important note
This article explains general principles. It is not a recommendation for any specific chemical. Suitable mixing rates and timing differ by substance, crop, growth stage and field conditions. Always treat the product label as the authority, and ask our staff or an agricultural specialist before deciding.