How High Does a Boom Sprayer Need to Be? & More: All Your Spraying FAQs Answered

If you work in agriculture, you’ll understand the importance of having to spray chemicals, such as herbicide, fertiliser and pesticides on your crops to ensure your yields are plentiful. However, when trying to cover vast expanses of land, such chemicals must be applied highly efficiently, which is where large-scale farm machinery sprayers, like a boom sprayer, comes in.

Choosing a type of sprayer isn’t always straightforward, though. Boom sprayers are one of the most popular types of sprayer, but they might not be the best option for everyone. In this post, we’ll provide some valuable insights into the most frequently asked questions about boom sprayers to help you make the right choice for your agricultural enterprise.

Get to Know the Basics of Boom Sprayers

Let’s begin with the basics to help you decide whether a boom sprayer is the most appropriate choice for your application.

What Is a Boom Sprayer?

If you’ve worked extensively within the agricultural sector, you may already know what a boom sprayer is, and you are probably sure to have seen one at some stage. For those who aren’t quite as familiar with the industry, a boom sprayer is the most commonly used type of equipment when it comes to administering herbicides on a large-scale farm. Essentially, it has large arms or booms with many nozzles that can spray out over a wide area of land, making spraying more efficient.

What’s the Difference Between Boom & Boomless Sprayers?

Again, while it may seem obvious to some, let’s establish the fundamental differences between a boom sprayer and a boomless one. Generally speaking, a boom sprayers is designed with just one or two nozzles that spray laterally in order to achieve adequate coverage over a large area. A boom sprayer is more complex in that it typically comes equipped with several spray tips, which are positioned along the booms (or arms) on each side with spaces between each nozzle. These nozzles aim downwards to ensure that chemicals can be sprayed directly onto the crops. Essentially, a boom sprayer allows for more accurate positioning, whereas a boomless sprayer allows you to spread the chemicals over a wider area more efficiently.

What Are the Benefits of Using a Boom Sprayer Over More Conventional Spraying Methods?

When it comes to spraying chemicals, fertiliser and herbicide on a large scale, there are several benefits to using a boom sprayer over more conventional spraying methods.

Superior Coverage

Naturally, when you are working across large expanses of land, you want to use a sprayer that works efficiently. Since boom sprayers operate closer to the ground, it is easier to monitor your work and track which areas have been sprayed and which areas still need to be tended to. Plus, the multiple nozzles makes it easier to cover a greater amount of ground in a shorter space of time.

Limits Crop Damage

On a related note, spraying efficiently so that you don’t spray the same area twice means that crop damage is reduced. Overspraying crops can significantly reduce your yield, which in turn has negative implications for your bottom line. It isn’t just cash crops you need to be concerned about, though. Sometimes growers accidentally overspray grass waterways which can lead to significant soil erosion.

Reduced Chemical Bills

As we’ve already established, conventional spraying is commonly associated with the overapplication of chemicals such as herbicides and fertilisers. In addition to the implications in terms of crop damage, overapplication is also a waste of chemical products, which has negative financial consequences for your enterprise. The automatic section control you have on a boom sprayer tackles this issue by allowing you to turn off sections of the boom or individual nozzles when you reach a part of the field that has already been sprayed. At the end of the day, this seemingly small detail can provide a great return on investment for farmers.

Better Wind Resistance

Compared to more conventional boomless sprayers, boom sprayers work more efficiently in adverse weather conditions when winds are strong. Since boom sprayers are positioned closer to the ground, the presence of the wind has less of an impact, and so the chances of chemical drift are reduced. This can also be combated by using a foaming nozzle, one with a heavier drip.

Do I Need a Boom Sprayer or Is It the Wrong Investment?

As is the case in most instances when you are dealing with large-scale farm machinery, boom sprayers can be a significant financial investment, so buying one isn’t a decision that should be taken lightly. Whether or not you need a boom sprayer really depends on the type of application you are required to do. Each application has different requirements for effective spraying.

Boomless sprayers tend to be great if you are working on rough, uneven terrain or are having to manoeuvre around obstacles such as fences or poles. However, when it comes to field spraying on level pastures, a boom sprayer is far more appropriate. However, Bunyip Equipment does have small boom sprayers that are purely to carry out domestic lawn care, so taking into account the size of the job and your machinery is paramount.

Boom sprayers tend to offer a greater level of wind resistance in terms of limiting chemical drift, so this is something else you should factor into your decision.

Answers to Some of Your More Complex Questions on Boom Sprayers

If you’ve decided a boom sprayer is a good choice for your agricultural business, we’ll now provide some more detailed insights to help you get to grips with some of the more complex aspects of this tool.

How Do I Successfully Calibrate a Boom Sprayer?

To get the most out of your boom sprayer, you’ll need to make sure it is calibrated correctly. It might sound complicated, but you’ll be pleased to learn that calibrating a boom sprayer is easier than it sounds. Plus, there are several ways to calibrate a boom sprayer, so you can choose whichever suits you best. And, whichever method of calibration you choose, it won’t take much longer than 30 minutes.

There are three pieces of equipment you’ll need to get the calibration done. First up, you’ll need some sort of timing device. You can either use your watch or a smartphone timer app. In any case, your timer of choice will need to display seconds. You will also need a measuring tape and a jar with mL markings.

To give you a good overview of what calibrating your boom sprayer entails. We’ll provide some details on the most straightforward calibration method for the broadest application. Here are the steps you’ll need to follow:

• Start by filling the sprayer tank with water until it is at least half full.
• To ensure your boom sprayer and all its vital parts are functioning correctly, it is crucial to inspect the sprayer for leaks by running it.
• Next, measure the distance between the nozzles on the boom.
• Now it’s time to measure the appropriate travel distance in the field based on the nozzle spacing on the boom. The appropriate distances for the different nozzle are approximately:
  • 25 cm spacing — 125 m travel distance
  • 40 cm spacing — 80 m travel distance
  • 50 cm spacing — 60 m travel distance
  • 75 cm spacing — 40 m travel distance

You’ll then need to drive through the measured distance in the field at your normal spraying speed, taking note of the travel time in seconds. To ensure you get this correct, repeat the procedure and take an average of the two measurements.

Once you park the boom sprayer, run it at the same pressure level and catch the output from each nozzle in a measuring jar for the travel time required. You then need to calculate the average nozzle output by adding together the individual outputs and dividing that figure by the number of nozzles tested, which will give you the final average output in mL equal to the rate of application.

Finally, compare the application rate you’ve calculated with the recommended rate. If the actual rate is 5% above or below the recommended figure, you’ll need to make adjustments in either spray pressure or travel speed to rectify this discrepancy.

What Nozzle Should I Use With My Boom Sprayer?

A boom sprayer is made up of several different components. The most important of these components are the nozzles, which split the herbicide into smaller droplets that can then be projected through the air onto the crops. The reason the nozzle is so important as far as the components of a boom sprayer are concerned is that it is the only part of the device that determines the effectiveness of the spraying capacity. All of the other components are secondary as they are just needed to secure the position of the nozzles and provide them with a regular supply of herbicide and pressure. It is therefore imperative to choose the correct type of nozzle if you want to use your boom sprayer to its optimal capacity.

How Far Off the Ground Should the Boom Sprayer Be?

When it comes to figuring out how far off the ground your boom sprayer should be, the nozzle fan angle does play its own part, as does the type of sprayer you are using. Most important, you need to ensure that the height of the boom sprayer is optimised to create the best overlap patterns. However, don’t forget about the risk of chemical defeat, which increases with boom sprayer height — the higher the clearance on your sprayer, the greater the risk of drift. If you do have a high-set boom, consider how this may undermine the benefits of certain types of nozzle design. Furthermore, if you are working with low-drift nozzles, you will need to ensure 100% overlap.

Looking for More Advice On Boom Sprayers?

Now that you’ve got a pretty good idea about boom sprayers, how they operate and the benefits of this type of machinery, it's time to head down to Bunyip Equipment, where we are ready to help with all your machinery needs.