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Lazing around instead of swinging the garden hose.
Automatic systems make this possible
Photo: Christin Klose / dpa-tmn
The best time to water the garden in summer is between four and six in the morning.
Then the ground has cooled down well after the night and the water hardly evaporates.
But who wants to get up that early every day?
This can be remedied by an automatic garden irrigation system, with which sprinklers and sprayers switch themselves on and off.
Thanks to smart technology, it can even detect whether rain is to be expected in the next few hours.
If so, then of course the water tap stays closed.
At what garden size is an irrigation system worthwhile?
An irrigation system can make sense for a garden area of 200 square meters or more.
The larger the garden and lawn area and the more beds, hedges and crops there are, the more advisable an automatic solution is.
Otherwise you would have to stand in the garden for hours to water it sufficiently, says Michael Henze from the Federal Association of Garden, Landscaping and Sports Field Construction in Bad Honnef.
Because the principle applies: »It is better to water less frequently, but more productively.
Then the water also reaches deep-lying roots.«
How do you install an irrigation system?
First of all, garden owners have to be clear about which plants they want to water and where.
»The be-all and end-all is an irrigation plan.
You can often create it online on the manufacturer's website," is Henze's tip.
But even garden professionals can help.
Important questions in advance: How long are the paths from the water point to the plants?
Where can you water vigorously, where does drip irrigation make more sense?
Can a central control system do this, or do you need a decentralized solution?
What information is important before making a purchase?
"I need to know how strong the pump and garden water pipe are, how many liters flow through per hour," says Jürgen Herrmannsdörfer from the Federal Association of Retail Gardeners in the Central Horticultural Association.
This value can be used to calculate how many sprinklers and valves can be connected to the line.
This applies to all systems.
It doesn't matter whether the watering is controlled by a timer or an app.
Is it worth laying the hoses underground?
It is not always worth laying hoses underground.
It is better to lay drip hoses or drip pipes above ground and then cover them with mulch, advises Herrmannsdörfer.
This protects them from sunlight and reduces evaporation.
If garden owners want to avoid tripping hazards, Herrmannsdörfer has a tip: »The distribution lines are usually laid at a depth of 20 to 40 centimeters.
Then they won't get in the way."
What do you need in addition to the garden hoses?
That depends on how sophisticated you want the irrigation system to be.
"In the simplest variant, a timer that is installed between the water connection and the garden hose is sufficient," says Michael Henze.
The timer controls the flow through a valve.
This allows you to set when and how long watering takes place, for example every twelve hours for 30 minutes.
Or an hour every three days.
A simple watering computer with multiple programs works in a similar way.
You can set weekdays and weekends, for example, or several passes in different areas of the property.
A sensor can help to respond more specifically to the plants.
It is installed at a reference point in the garden.
"It measures the soil moisture and sends the corresponding signals to the control center," explains Herrmannsdörfer.
"After heavy rain, the water only comes on again when the set value is reached."
When is an irrigation system smart?
Smart systems act largely independently.
"An irrigation control that opens and closes the valve is connected directly to the water tap," explains Sebastian Klöß, division manager at the digital association Bitkom.
To do this, the controller receives instructions from the control center, which processes information from various sources – for example from a humidity sensor, temperature sensor and light sensor.
"Using all this data, it calculates when and how much watering needs to be done," explains Klöß.
The robotic lawnmower can also be integrated.
The device then only starts if the lawn is not too wet.
All of this can be operated via mobile phone or tablet.
If you want to control the irrigation in the garden remotely, you have to connect the control center to the Internet via a router.
Klöß says it would then also be possible to include external weather data.
By Katja Fischer, dpa
