Begin with Nozzle pressure

I know - it's not normal practice to begin your calibration process with nozzle pressure but here's why I think it's so important.

Bear with me on this one - You know how you get frustrated at times with those golfers who don't understand the complexities of your job, when they mistreat your hard work and ignore your requests?? Well there is a nozzle designer out there somewhere that feels exactly the same about you!

A quick google search shows how much work goes into designing nozzles

So how do we get the best out of them? As with many things they are designed to be very generic (except the Syngenta XC nozzles which are designed specifically for turf) so they have some flexibility built in.

In turf there is very little variables in the crop we spray - 3mm to 25 mm is fairly insignificant compared to cauliflowers - barley.

What are the key things we are looking for

Good coverage

This is absolutely critical. Consistent coverage is only achieved once a nozzles low end optimum pressure is reached. Not as critical in other crops as turf so have a look and asses that yourself. It's unlikely the nozzle chart will give you a good indication.

Minimum Drift

We don't want to lose any product both from an environmental standpoint and getting the very best out of any product we've purchased. ALL nozzles will have an element of fine droplets at all but the lowest pressures but you have a lot of control over the ratios of fine to coarse by adjusting the pressure.

Leaf deposition

When applying any product you should have a pretty clear idea where on the plant you want it. Do you want it on the leaf or in the soil?

(Want to be an Application Expert, take a look at our new Application Academy that we're launching at #BTME2020).

Despite popular belief it's not simply down to water volume - if you increase water volume by upping pressure you increase the amount of fine droplets which have a higher chance of "sticking" to the leaf, the lower the pressure the higher chance there is that the coarser droplets will run off the leaf towards the soil.

The reality is that your two biggest priorities are excellent coverage and minimal drift. Achieving full spray pattern sets your minimum pressure limit and the commencement of drift sets your upper limit.

That gives you a fairly narrow pressure band in which to get the best of your nozzles.

If you want to adjust water volume of retention on the leaf - my preference is to use forward speed and / or nozzle size to adjust - optimum pressure for me is the foundation to good application.

Confused by the complexity of nozzle charts? Me too. In this blog I try to make sense of them - Making sense of Nozzle Charts

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