How can I water trees properly?

Do we really have to water our trees? The rain is responsible for that. In principle, that is correct. But our earth has been suffering from long dry periods for many years. This means that the rain stays out too long and our trees die of thirst without support.
It is therefore important that we help our trees and, by watering them properly, give them a refreshing tree bath. But what types of irrigation are there? How do trees store water and how are they properly watered? You can find the answers here.

Table of Contents
Why do we really need to water our trees?
How exactly does a tree absorb water?
How do trees store water?
How much water should you water trees with?
How often should you water trees?
Watering trees - an overview of the various irrigation methods
The garden hose and the watering can
The drip irrigation
Sprinkling as a watering method
At what times of the year should a tree be watered additionally?
Watering trees in winter
Watering trees in spring
Watering trees in summer
Trees water in autumn
Our watering recommendation
More tips on watering trees

Why do we really need to water our trees?

Due to climate change, there are increasingly long periods of heat and drought. This means that there is no rain for a long time, the ground becomes extremely dry and our trees are very thirsty. This so-called Drought stress can ultimately lead to tree death.

You can recognize drought stress, for example, by withered leaves, premature leaf fall or dying branches. At the latest, you will notice that your tree urgently needs water.

You can find more about the causes and consequences of climate change in a separate article:
Climate change - the greatest challenge of our time

How exactly does a tree absorb water?

Our trees can drink by absorbing water through their roots. This water is then transported from the roots through the trunk and branches to the leaves. The roots of our trees extend differently far and deep under the ground.

Here we differentiate between shallow roots, deep roots and heart roots. The root system of the Shallow roots is, as the name suggests, very flat under the earth. The water uptake takes place mainly via the surface water, which seeps through the earth.
The roots of the Deep roots are grown very deep in the ground. The water is mainly absorbed from the deeper regions, as a main root drifts towards the groundwater.
Heart root in turn combine both skills. Some of the roots grow diagonally downwards and can branch out sideways at the same time and therefore absorb the water in different ways.

How do trees store water?

Similar to us humans, trees store water in every single cell. The water supply is in the roots, in the trunk, in the branches, in the leaves and also in the fruits. The bigger the tree is and the more leaves, needles or fruits it has, the more water it can store. When this reservoir is fully filled, our trees can survive for a long time without an additional water supply.

However, due to the long dry periods in recent years, the trees' water reserves have been used up and a natural water supply is no longer possible. If the memory is empty, the tree goes into emergency mode. The leaves dry up, are shed and the whole tree dries out.

How much water does a tree need?

There is no general answer to this question. The amount of water always depends on the size and location of the tree. A medium-sized tree around 5 to 6 years old is happy about 150 to 200 liters of water per irrigation session. This corresponds to around 2 to 3 filling quantities of a 75 liter irrigation bag.

How often should you water trees?

Trees especially need support when it is very hot and dry for a long period of time. You can help the trees best if you tell them something twice a week treat yourself to a tree bath. This feels much better for the tree than giving it a small amount of water every day.
It is ideal if the trees are watered in the morning.

Watering trees - an overview of the various irrigation methods

We can support our trees with different irrigation options to quench their thirst. There is no wrong or no right way to do this. Every single drop of water helps the trees. However, there is a special watering method that you can use to support your tree particularly well.

The garden hose and the watering can

Watering can and garden hose are the classic methods of watering trees. You can use tap water or rainwater collected from the rain barrel for this. For the tree, however, watering with a hose or watering can means a real flood of water at once. The water drains away so quickly that the roots hardly have the opportunity to absorb it. Just imagine that you are very thirsty. Then someone pours a bucket full of water over your head. Can you drink enough of it in this short time that your thirst is quenched?

With the garden hose, you never know how much water you have supplied the tree with.

The drip irrigation

To properly water trees, we recommend drip irrigation. By this you can understand a form of long-term irrigation. Here, small amounts of water are evenly released to the roots through small openings on watering bags, hoses or pipes. This type of irrigation is possible both above and below ground.

Drip irrigation has the advantage that the roots get enough time to absorb the water and thus supply the whole tree. At the same time, thanks to the watering bag, you always know exactly how much water your tree is being supplied with. Water should not be wasted, especially because of the increasing drought.

You can find a lot more information about drip irrigation in the separate article:
"The drip irrigation in detail"

Sprinkling as a watering method

By sprinkling you can understand the open spraying of water over a large area. With this type of irrigation, the water supply in the soil can be optimized so that the roots are supplied with water even during a dry season.

As already discussed, any kind of support for trees is helpful. However, when irrigation occurs, there is a high evaporation loss of water, especially at high temperatures.

At what times of the year should a tree be watered additionally?

Due to ongoing climate change and the associated changes in temperatures and precipitation, dry phases can always occur, regardless of the season.

Watering trees in winter

In the winter months, the trees are in a regenerating dormant phase and usually do not need any additional watering. But in recent years it has been shown that there is less and less precipitation even in the winter months and that the soil moisture in some regions also continues to decrease at this time of the year and the groundwater reserves can no longer be replenished to a sufficient extent. With consequences for the water supply of the trees in spring.

Watering trees in spring

After the mostly rainy months of January and February, it is becoming increasingly common for our trees to need additional water in March and April. An adequate supply of water is extremely important for trees, especially at the beginning of the growing season. In this phase, the trees want to produce shoots and lots of leaves. And if they don't get enough water here, growth will be immediately delayed. Depending on the amount of precipitation in March and April, it is helpful or even necessary to support the trees at regular intervals.

Watering trees in summer

The summer months of June to August are months in which it may well be necessary to regularly support a tree. Especially young trees and city trees with smaller roots than older and free-standing trees sometimes need our support several times a week.

You can find more about watering city trees in the separate article:
"How to properly water and save city trees"

Trees water in autumn

From September onwards, a tree usually only needs support if it has shown signs of drought stress in the previous months. As autumn begins, the trees slowly lose their leaves and prepare for regeneration. But here too it is still necessary that they have enough water, as in this phase they still produce secondary plant substances to ward off pathogens and pests.

Our watering recommendation: drip irrigation

In the opinion of our group of experts, drip irrigation is the best way to water trees optimally. Other pouring methods are always well intentioned and also help a little. Nevertheless, too much water is usually lost or does not even reach the roots.

The irrigation bags are designed precisely so that the water is delivered to the roots drop by drop. And at the same time, due to the capacity of 75 or 100 liters per bag, they enable you to water with a large amount of water in one watering session. This means that the water reaches where it is needed in a quantity that is comfortable for the tree.

More tips for watering trees:

Water and especially drinking water is a valuable resource that we should use sparingly. So here are a few tips for watering. So that as much of the water we use for watering as possible reaches the roots and thus the tree.

Water as early as possible in the morning.

When watering in the midday and afternoon hours, more water evaporates than in the morning hours. And due to the lens effect of the water drops, other plants in the area of ​​the tree disk and roots on the surface can burn due to the stronger solar radiation.

Watering in the evening, on the other hand, promotes fungal infestation on plants and attracts snails. Both have less immediate consequences for the tree. But all the more for the surrounding plants.

It is better to water a larger amount once than just a few liters a day.

Smaller amounts of water only penetrate the soil superficially and are usually not enough to moisten the entire soil so that the water also reaches the roots. It is therefore better to do fewer waterings and to give a lot of water per watering. 150 to 200 liters with 1 to 2 watering sessions per week are optimal. It is also important that the water is released slowly to prevent it from seeping through the root area.

Periodically loosen the soil around the tree.

Especially with city trees, but also with trees in many gardens, the soil around the tree is often very compacted. As a result, the water often flows off the surface when watering and evaporates. Loosened soil, on the other hand, absorbs water better, so that more irrigation water reaches the roots.

If possible, use process water or rainwater for watering.

On the one hand, trees and other plants in the garden like "soft" low-lime rainwater much better than tap water. On the other hand, drinking water has to be treated and cleaned in a complex manner. Therefore, where possible, service water or rainwater collected via cisterns, rain barrels or water diversion systems should be used for watering instead of drinking water.