When you return from vacation, the garden is a sad sight. The grass has yellowed, many plants have withered. Autumn has already started for the blackberry bush: the leaves are changing color and the fruits are dried up and inedible on the branches. Some trees let their leaves hang despondently. Only the lavender and oregano bravely resist the drought.
The vast majority of Dutch houses have a garden, so the question is: how can a tragedy like this be prevented, now that hot and dry summers will become more frequent due to climate change?
There is no such thing as careless spraying. Not at a time when the shortage of water is already so palpable, when, thinking of Holland, we don’t see wide but narrow rivers flowing slowly through endless lowlands, when farmers suffer from crop failures because they have to limit their water use, and when nature craves for a rain shower.
yellow grass
Fortunately, spraying is not always necessary. ‘We no longer put sprinklers on the lawns, because for us the lawn doesn’t have to be one of those classic English billiards’, says Gerard van Buiten, hortulanus (head gardener) of the Botanical Gardens at Utrecht University. ‘Just let the grass turn yellow. If there is a heavy shower, it will be green again in no time.’
Speaking of grass, it’s better not to mow it too often. Van Buiten: ‘The growing point of grass is just above the ground. If you mow it too short or too often, it will be in full sun and it will burn. So it’s better to keep the grass a few centimeters higher.’
For the rest of the garden, Van Buiten recommends ‘a Spartan upbringing’. ‘Don’t spray too quickly. Only if a plant has just been planted do you have to help it a bit. But after that, it’s better to give it a lot of water once a week instead of watering a little bit every day. In this way the plants will make deeper roots.’
false indigo
It is also worth choosing plants that can withstand a more Mediterranean climate. Lavender and oregano, indeed. Or rockrose and false indigo. ‘Once the latter is in place, it will never need a drop of extra water again’, says Van Buiten. He prefers to advise people to take a tour of their own neighbourhood. ‘You must have the plants in every garden. These are plants that do well in your area, on your soil type. After all, it makes quite a difference whether you sit on sand or clay: on sand the water washes away quickly, clay retains water longer.’
Climate change is making it hotter and drier on the one hand, and climate scientists also expect heavier showers on the other. People with a garden can make use of this, believes Floris Boogaard, consultant at the Deltares engineering firm and lecturer in Spatial Transformations – Water at Hanze University of Applied Sciences Groningen. ‘For example, collect water in a rain barrel. In many municipalities there is a subsidy available for this. Such a rain barrel helps to reduce water use, and it also contributes to awareness: water is a scarce commodity.’
And that is necessary, Boogaard analyses. The Netherlands has always been a country that has been busy draining water quickly, but now a change has to take place. ‘We need to retain water longer. Every drop that does not flow into the sea through the sewer is a profit. Let the water seep slowly into the soil: tiles out, plants in. Or build a wadi: a low-lying spot in the garden, where it can be a bit wetter without any problems.’
water wall
Boogaard is a collector of creative solutions. He sees, for example, that people direct the water to the hole under their trampoline. That they make a rain barrel from a discarded garbage container. Or that they build a ‘water wall’: a series of vertical downspouts next to each other, which together serve as a high, narrow rain barrel.
‘Ultimately, you have to arrange your garden in such a way that you don’t use more water than you can collect yourself,’ says Boogaard. ‘And don’t think: my garden is small, what I do makes no difference. Even in the cities more than a quarter of the land private property. We really have to work on that ourselves.’
And not with a groundwater pump, emphasizes both Boogaard and Van Buiten. ‘We may have once thought that the groundwater in the Netherlands was infinite, but that turns out not to be the case,’ says the hortulanus of the Botanical Gardens.