Terry has worked in a gardening-related industry for the past 18 years and has always worked hard to ensure his clients have the best experience...
The hydroseeding spraying technique that you use is not something that you should get too hung up on and shouldn’t affect the finished lawn. With hydroseeding, what is more important than the technique is the evenness, volume and accuracy of the slurry distribution.
Having said that there are several techniques that are usually employed when spraying the hydroseed slurry and they can be used in isolation or in combination with each other. These fall into two categories handheld and platform spraying.
We will look at the two categories separately and within each, look at the techniques that can be employed to get the most even and accurate distribution of slurry.
Hydroseed Spraying Techniques With a Hose
In terms of residential jobs, the method that is most likely to be used is a manual method, utilizing a hose. This is usually done but one or two people, depending on the size and length of the hose. The hydroseeding slurry is pumped through the hose and sprayed via a nozzle attached to the end of the hose that can be open and shut.
There are primarily two different techniques that can be employed to spray using a hose, either spraying out or spraying downwards. There are factors that affect this choice and indeed the position at which you hold the hose and nozzle most notably the size of the nozzle.
Probably the most common method employed is the spraying out method. A lot of contractors choose to sprat with the hose over their shoulder and the nozzle positioned horizontally, at a 180 angle. Positioning the hose and nozzle in such a way gives the contractor more control. A variation is to hold the nozzle around the hip level and spray from here.
The effect of spraying in this way broadcasting the slurry over a wider area and building up the mulch in layers. Spraying out means a wider area is covered in a shorter period of time. It allows you to build up the thickness of mulch that you are going to put down and the mulch will protect the seeds from the sun.
The second method is to spry directly at the ground. Much in the same way that you spray horizontally you can either rest the hose and nozzle on your shoulder, which provides a great pivot to anglew the hose downwards, towards the ground.
The advantages of spraying dowwards is one of accuracy and as the distance from your shoulder to the ground is short, the pressure will force the seeds deeper into the soil which allows the seeds to have better water retention then if they are within the mulch on the soils surface.
The disadvantage of spraying down is that the mulch also is forced into the soil lessening its ability to protect the seed from the sun. In addition, although not crucial in terms of the resulting lawn, the visual impact on the area after the hydroseed slurry has been applied wont be as vibrant (the effect of the green dye added to the hydroseed mix) as if you sprayed out.
Combining Spraying Out and Spraying Down
In reality the two techniques are often combined. This is, particularly the case if there is an extremely large area to cover. Spraying out is a far more efficient method of covering a large area than spraying down.
But there are times when precision is necessary and particularly when trimming you can control the spay more accurately when looking to cover a narrow target area.
By combining the two methothod you are likely to get the best results than by solely using one method over another.
Size of Nozzle
Whether you spray from the hip or the shoulder will likely depend on the control you have in both positions. This, in itself, is going to be determined by the size of the hose and nozzle. The bigger the hose and nozzle the greater the volume of slurry that can be distributed per second.
The bigger the hose and nozzle though, the more unwieldy and less control you are going to have. If you are using a larger nozzle then it is more than likely that you will have to adopt the over the shoulder method for spaying in order to exert enough control to get an even distribution. This might be particularly important in terms of trimming.
Nozzle Manipulation: Trimming
Trimming is the process that is used to achieve accuracy when spraying a target area so that you get relatively clean lines and edges around paths and other obstacles, or adjacent areas bordering the hydroseeding zone.
Trimming is done using the spraying down technique in conjunction with manipulating the appature of the nozzle. By incrementally closing the nozzle appature you can gradually reduce the spray arc and a achieve a fine spray which will allow much more accurate and fine spraying.
If you need to be supper accurate with your spraying you can use cardboard or thin plywood board, to mask off the are you don’t want the slurry to cover.
When spraying thicker mulches and or vast areas, you generally need bigger hydroseeding machines. The bigger machines have larger capacity pumps and turret mounted guns that can spray over vast distances. They can cover the target area far more efficiently than a hose and nozzle, without the machine needing to move around too much.
The turret gun sprays in the same manner as the manual spraying out method with house and nozzle. You would look to build up the levels to get the required thickness of slurry.
The disadvantage of the turret gun is that, because you a spraying over vast distances, it can be quite hard to control the narrowness of the spray arc. This means that it can be difficult to be too particularly accurate as the distance that the slurry travels means that it will spread wider than the spray arc on landing.
Summary: Hydroseeding Spraying Techniques
There are standardized techniques that are used to spray the hydroseeding slurry. These methods have come about largely because they seem to be the easiest and most practical way for the hydroseed to be sprayed.
This doesn’t mean that they are the only way. The most important things are the evenness and volume of the slurry distribution, combined with the spraying accuracy. In general, hydroseeding is highly forgiving and the likelihood of success is fairly high as long as you have a sufficiently even application and apply the slurry at a reasonable volume.