Taking a few hours to properly prepare your sprayer for winter storage is essential to avoid costly frost damage and can add years to its life, says agricultural engineer Ben Strathern.
“As we bid goodbye to an exceptional summer and autumn, the North of England has already seen its first snow and growers must now ensure that sprayers are ready for a drastic drop in temperature,” said Ben, who’s Essex-based company B R Strathern specialises in viticultural machinery and equipment. “The majority of sprayer problems and breakdowns we come across are a direct result of poor winter maintenance, all of which can easily be avoided by following some simple steps.”
Rinse
The whole sprayer system including the tank, hoses, filters and nozzles, should be rinsed thoroughly to prevent corrosion, product cross-contamination and clogging of nozzles. Chemical residues in nozzles can not only lead to changes in flow rates, but can alter spray patterns, resulting in uneven distribution of chemicals on the target.
“Clean water should be circulated through the sprayer, with the nozzles off, before being completely flushed out preferably in the vineyard, or somewhere where the rinsate cannot contaminate water supplies,” said Ben. “It is more effective to rinse several times with a small amount of water than to fill the unit to capacity.”
Clean
After rinsing the system, the unit will need to be cleaned inside and out with a pressure washer. Growers can also opt to run a detergent through the system to ensure that it is thoroughly decontaminated, although remember that the sprayer will need re-rinsing afterwards.
Inspection
The end of the season presents an ideal opportunity to take a once over look at the sprayer for any wear and tear as there is plenty of time to order and fit any required parts.
“Growers should be checking the tank for cracks, the nozzles for wear and the hoses for any leaks,” said Ben. “The pump should be oiled and rotated, and it is well worth testing the unit’s ability to hold pressure. If there are any problems at this stage the diaphragm, valves or seals in the pump should be inspected for damage.”
If using a trailed sprayer, check the wear of the tyres and that the amount of play on the steering is at a minimum. Make sure that the fan guards and PTO chains and guards are not damaged or missing. It is also vital that any illegible or missing warning stickers are replaced.
“Check all switches and controls are working as expected,” said Ben. “Those operating sprayers with electrical controls should also double check the fuse as these can often void the warrantee. If in doubt, contact your local dealership or mechanic and book it in for a full service.”
Anti-freeze
Distributing anti-freeze through the whole sprayer system will help to curb any frost related damage and corrosion.
“The cost of anti-freeze is miniscule in comparison to the costs of repairing a cracked pipe or pump which can cost £1,000s,” said Ben. “There are plenty of good anti-freeze concentrate products for field sprayers on the market and ones such as Granit will protect down to
-25 °C.”
The anti-freeze should be flushed through the system until you can see it spraying from the nozzles. This will ensure that there is no residual water left in the system and that everything is lined with a residue of anti-freeze to prevent cracking and damage such as rusting. Growers will need to remember to clean and rinse the system before its first use next season.
Storage
Ideally, the best way to ensure that your sprayer will be protected from rust and frost damage is to keep it in a dry warehouse or barn. If, however, space is at a premium, growers should remove all pipes and hoses, and suitably cover the sprayer unit so it is not directly up against the elements.
