Background considerations

1. Existing and future farm policy and equipment.

Existing and future farm policy will dictate the area, variety and rotation of the crops to be sprayed; different crops will have different spraying requirements, such as types of chemical, application rates and the timing of applications.

2. Timeliness.

Timeliness of spraying is very important to the grower, pesticides must be applied at the correct time to ensure their success. The following points will affect timeliness of application

• area to spray per season,
• frequency of spraying,
• land characteristics,
• weather
• workload of the farm.

3. Alternative spraying techniques

Growers need to consider novel sprayer designs such as directed deposition sprayers. Each new design needs to be carefully assessed, do the benefits outweigh the extra costs? With increasing legislation concerning the environmental aspects of pesticide application, techniques which improve deposition, reduce drift and reduce tank rinsate must be considered.

4. Modify an existing sprayer 

Many modern components for updating sprayers can be bought via catalogues or via the internet and can be supplied by nozzle manufacturers and specialist component manufacturers.  These very comprehensive catalogues or web pages are illustrated with excellent diagrams to aid on-farm sprayer modification. A number of manufacturers offer electronic aids which help monitor the sprayer, self-fill hoses, chemical probes, etc.

5. Home construction

If the farmer is mechanically-minded or has a competent mechanic and a lot of spare time, one may consider making ones own sprayer. Sprayer component catalogues are a most useful source of information to aid the construction of farm sprayers. The alternative to making a sprayer oneself is to commission a sprayer from a manufacturer; a number of manufacturers will construct a sprayer to the clients specification

6. Custom application

Growers based upon small acreages should consider the role of the custom applicator before purchasing a sprayer. Alternatively, a grower, after purchasing a specialist sprayer, may have time to establish a business as a custom applicator and thus help spread the high costs involved.

Aerial spraying is normally a specialised contracting service and can be financially attractive to some farmers, particularly when early applications are required.