Backpack sprayers being discussed by John Grande, Ph.D., from the Rutgers Synder Research and Extension Farm.
Most farms have at least one backpack sprayer. They are cheap to buy, easy to run and are an efficient way to get the sprays on the crop. My farm is small enough that I will probably never use a tractor-mounted spray rig but we put the two backpack sprayers that we have through their paces during our season. While most of the time we are spraying a fish/kelp mix to feed the crop, there are times where we try to kill bugs or prevent disease. An “out of the box” sprayer lacks a level of consistency that can be really important when it comes to applying some of the protectants that are available to organic growers. Just because it’s organic doesn’t mean it’s safe if you misuse it. There are lots of products available to us that have very strong active ingredients and they should be applied in a way that is consistent with their label. Not only for the safety of the farmer, but for the safety of your workers, other non-targeted and beneficial insects and animals that live on your farm, and your downstream neighbors. Lastly, we only have a few active agents that we can use as organic growers, and if we misuse them, their efficacy will diminish, and we will have fewer tools for our farms. In 2011 I went to the New England Vegetable and Fruit Conference in Manchester NH, and there was a presentation on “Optimizing the Use of Backpack Sprayers for Pesticide Application,” presented by John Grande of Rutgers University. He talked about the testing that he did of different models of sprayers and explained his methods to calibrate them so they put down a consistent amount of product.  I will be converting my spray rig this spring with a pressure regulator and a better set of tips. My intention was to document this conversion for this article but I think that the information will be most useful to you firsthand.  Fortunately, there is a source that documents the whole conversion procedure, and it’s an amazing resource. I encourage you to follow this link and check it out. All the info you need is here, and there are great videos as well. My thanks to John Grande and Jack Rabin of Rutgers University for developing this link: http://snyderfarm.rutgers.edu/snyder-backpack-sprayers.html Of course, now that you are ready to go spray with your new rig, make sure that you are on the right side of the law. Here’s a link to an article I wrote a while back about the Worker Protection Standard. I hope the season is going well for you and your farm. Paul