Follow these directions to use the Spot-Spitter in your nursery or tree farm
The Primerus Spot-Spitter spray stake, also known as the Roberts Spitter, is the nation’s leading irrigation device for large container nursery growing. It’s the emitter of choice for nursery containers 5 gallons and up and is used by most of the nation’s top nurseries and tree farms.
The Spot-Spitter is a simple plastic stake with a grooved peg on the end. Put a piece of 1/8” Spaghetti Tubing over the peg and a stop leaves the bottom of the groove exposed as shown below. When you pressurize it, water will come out of the exposed part of the groove, bounce off a splash plate, and create a mini spray pattern just the right size to irrigate your container without overspray.
Do this by simply cutting the other end of the spaghetti tube at 45 degrees for a sharp point. Then poke a hole in your poly hose supply lateral using a Primerus Hole Punch, and insert it to create a water-tight seal without the need for a barbed fitting. Now you’re ready to put your Spitter in the container and turn the water on. Just like that.
The individual-container spray pattern gives you the precision that can’t be achieved with overhead sprinklers and full-container root development that can’t be matched with drip. Also, each Spitter is highly resistant to clogging from dirty water. But if it does get clogged, simply remove the tube, wipe it off, put it back on and you’re up and running again – something you simply can’t do with any other micro-irrigation device.
It’s important that you use a pressure regulator to keep pressure between 15 and 25 psi, and you need to be sure you don’t exceed the maximum number of Spitters on each row that your lateral can supply with good uniformity. This number depends on operating pressure, your lateral tubing diameter and your specific Spitter model. Primerus provides a Design Tool on their website that can help you with this, or you can use the printed Instructions for Use that come with each bag of Spitters. Grow Irrigation has other articles that give details on how to do this.
If you are a successful nurseryman, you likely sell your plants with each season. If you use the Spot-Spitter, when you take a container out of service you simply flip it over and put the tube on the other end to shut it off. The peg on the reverse side doesn’t have a groove, so water stops flowing. Another nice feature is a Directional Nub that indicates spray-direction so you can use feel to install them quickly and in the right direction.
Finally, the Spitter is made from a single piece of UV inhibited super-tough acetal and is virtually indestructible. Chances are you will lose your Spitter or retire and sell your nursery before it reaches the end of its useful life.
There are seven different versions of the standard Spot-Spitter. Each one is a different color and flow rate. A simple chart tells you which color to use based on container size.
Use the Orange mini-flow for 1-3 gallon containers. The light green is good for 2-7 gallon and the dark green is for 5-15 gallon containers. Some growers will use two dark greens in a 30-gallon container or 24” box. Finally, the high flow Black, at 15 gallons per hour, can irrigate your 15-25 gallon containers. Many growers use 4 blacks in a 36” box to apply a full 1 gallon per minute with good uniformity.
You’ll notice there’s some overlap in the container recommendations for each color and it’s not an exact science. Some growers with a few different container sizes choose to do it all with one color to avoid mistakes that can happen when installers put the wrong color into the wrong container.
That’s all you need to know to get started with the Spot-Spitter in your nursery. Keep an eye on our website for more articles about nursery irrigation - and always, feel free to contact us at info@GrowIrrigation.com for more information.
With thanks to Primerus Products, LLC for use of content in YouTube video “Introduction to the Spot-Spitter”