The best time to water the garden in summer is in the early morning between four and six o'clock. That's when the soil has cooled down well after the night and hardly any water will be lost through evaporation.
But if you find the prospect of setting an early alarm every day a bit irksome, technology can help.
An automatic garden watering system will turn the sprinklers and sprayers on and off by itself. It can even detect whether rain is expected in the next few hours, and limit the water supply accordingly.
An irrigation system can make sense for gardens with an area of 200sq m upwards. The larger the garden and the lawn, and the more beds, shrubs and plants there are, the more advisable an automatic system is.
Otherwise you would have to stand in the garden for hours to water it properly, says Michael Henze from Germany's Garden, Landscape and Sports Ground Construction Association.
"It is better to water less frequently, but more abundantly. Then the water will also reach deep roots."
First of all, garden owners need to be clear about which plants they want to water and in which places. "The most important thing is to have a watering plan," says Henze. "You can often draw one up online on the manufacturers' websites." Professionals may also be called in to help.
It's important to know the distance from your water source to the plants. You should also establish which plants need a heavy supply, and which will thrive with drip irrigation.
"You need to know how strong the pump and the garden water pipe are, and how many litres pass through per hour," says Juergen Herrmannsdoerfer, from the German Association of Retail Gardeners.
This will help you to calculate how many sprinklers and valves you can connect to the pipe, irrespective of whether the irrigation is controlled by a timer or an app.
It is not always worthwhile to lay your hoses deep under the ground. Drip hoses or pipes work better on or near the surface, covered with a small layer of mulch, according to Herrmannsdoerfer. This, he says, will protect them from sunlight and reduce evaporation. "The distribution pipes are usually laid 20-40cm under the soil surface, so they're not in the way."
"For the simplest watering system a timer that is mounted between the water connection and the garden hose is sufficient," says Henze.
The timer regulates the flow through a valve. This allows you to set when and for how long to water, for example every 12 hours for 30 minutes. Or one hour every three days.
A simple watering computer with several programmes works in a similar way. You can set weekdays and weekends, for example, or set different schedules for different parts of the garden.
A sensor can help to target the plants more precisely. "It measures the soil moisture and sends corresponding signals to the control centre," says Herrmannsdoerfer. "After heavy rainfall the water only comes on again when the set value is reached."
Smart systems act largely independently. "An irrigation controller is connected directly to the water tap, which opens and closes the valve," says smart home specialist Sebastian Kloess.
To do this, the controller receives instructions from the central unit, which processes information from various sources – for example, from moisture, temperature or light sensors.
"It calculates how much watering is needed for you," explains Kloess. Robotic mowers can also be integrated into the system – they will only start working when the lawn is not too wet. All this can be operated via a mobile phone or tablet."
If you want to control the irrigation in the garden remotely, you have to connect the control centre to the Internet via a router instead of via WLAN. This will enable you to include external weather data. – dpa
Apply Lazada Voucher to save more on your garden purchases