Targeted irrigation: Choosing between sprayers and drippers?

A beautiful garden or a lush lawn needs regular watering in order to stay healthy all season long.  Watering the garden by hand though can become time consuming, especially in the height of summer when the watering demands increase.  

Taking the time to set up an irrigation system in the garden can be time saved in the long term, with the added benefit of reducing water wastage since you control where the water specifically goes and how much gets distributed.

There are irrigation options to suit every garden but the abundance of choice can be quite overwhelming when having to decide what kind of irrigation system you need. Deciding when it is best to use sprayers or drippers is an important factor in irrigation success. Here is a quick break down of the differences between sprayers and drippers to help you decide what is best for your garden:

SPRAYERS

Sprayers are best suited to large areas like lawns or large garden beds and will indiscriminately wet everything in its reach including the soil and the entire plant.

Within the sprayer range you can have control over the area you want watered and even how vigorously you would like that water delivered.

Most sprayers have the option of spraying in a full, half or quarter circle or even in a narrow strip so you can ensure that only the garden or lawn is watered, and paths, walls and fences are left dry.  

Sprayers also vary in the type of spray that is given off, from small droplets in a fine mist to a robust sprinkler effect with larger droplets.

The various sprayers also vary in the distance the water is distributed across your garden and also the pressure that is it delivered. There are fixed and adjustable versions available allowing increased flexibility when setting up your irrigation system.

Deciding on which sprayer you need depends on what you are trying to spray.  A fine mist or a gentle spray can be great for seeds and tender young seedlings and for plants that enjoy humid conditions such as fern and, of course, delicate plants that can be harmed by vigorous watering.  Whereas a sprinkler spray is more suited to a lawn or large garden area. 

Considerations:

While there is a wide range of sprayers for every situation there are a few downsides to be considered:

• Watering this way can result in loss of water through evaporation, run off and water being blown away.
• Watering the leaves of the plant can create humid microclimates making the plants susceptible to fungal diseases.
• As everything in range is watered, you can encourage the growth of weeds.
• To ensure even coverage extra effort is required to plan out the ideal irrigation system layout.
• As plants grow, they can interfere with the spray pattern and block water from their neighbours.  

DRIPPERS

Drippers deliver water in a more specific way, as the name suggests, dripping water near individual plants and specific areas.  They also come in a range of styles to suit their intended location and water pressure and also include adjustable drippers so you can adjust the area being watered.  

Drip irrigation is slower than spray irrigation but delivers the water directly to the soil and the roots so there is much less water loss to evaporation and the plants stay dry, so the risk of fungal disease is greatly reduced.  Allowing a good steady drip at the roots for a longer period of time will encourage the roots to grow deeply and become more resilient in dry periods. 

As well as for specific plants like shrubs and trees, dripper irrigation is great for container and hanging baskets.

Drip line hoses, with evenly spaced drippers are a great way to water larger areas such as vegetable gardens, annual flower beds and hedges. As an added bonus, drippers work well with low water pressure.

Considerations:

While drippers can be a great choice, they have a few drawbacks.

• They aren’t suitable for large areas such as lawns.
• They can become blocked with dirt, grit and insects and require checking and cleaning from time to time to ensure the system is working well.  

Once you have decided which option is the right one for you there are a few more points to consider:

• Ensure your water supply has enough capacity to support your sprays or drippers. Perform a bucket test to determine your water flow rate which will help you determine the number of lines you require. 
• Don’t mix drippers and sprinklers/sprays on the same line as they have different flow rates. 
• Don’t use too many drippers or sprays on one line as this will reduce performance. 
• You might want to consider a “set and forget” approach by adding an electronic tap timer to your system.