Water trees in summer

Table of Contents
Summer: the highlight of the growing year
Watering trees correctly in summer
The correct amount of water
The correct casting method
The right time of day
Recognizing drought stress
Fertilizing in summer

Water is life. With enough water, trees can photosynthesize, thrive, defend themselves against diseases and pests, and repair themselves. If there is one thing we should do really well with trees that have already been planted, it is watering. There are different challenges for every season. Here you will find the most important knowledge for the summer.

Summer: the highlight of the growing year

In summer, the trees receive the most sunlight and can therefore carry out a lot of photosynthesis. Through photosynthesis they can make sugar molecules and then use them for fruiting, growth and repair. It is also the time when the trees create reserves and store sugar for the darker seasons.

However, trees can only photosynthesize if they have enough water available. If they lack water, they must close their stomata (small openings in the leaves) and thus stop photosynthesis. Therefore, in the absence of water, trees cannot produce the sugar they need for growth and survival.

In addition, many other important chemical processes can only take place with water. If there is a lack of water, trees have difficulty defending themselves against pests and diseases, for example. And because the trees evaporate a lot of water in summer, the risk of drought stress is particularly high here. Watering trees is therefore very important, especially in summer. 

How do I water correctly in summer?

In dry and hot summer weeks, all trees probably appreciate additional watering. Do you have a tree that you would like to harvest fruit or nuts from? Then it's worth making sure that the tree has enough water, especially now in summer.
Young trees, especially those planted within the last five years, require additional watering during the summer. Their root systems are not yet sufficiently developed to reach the deeper layers of soil.ßen. Young and newly planted trees are therefore much more susceptible to drought damage.

 Therefore, make sure these young trees get enough water, especially in summer. If it's dry for an extended period, you can water them with 150-200 liters once or twice a week.
Trees under three years old can be watered 3-4 times a week during dry periods. However, be careful not to overwater them, as many trees cannot tolerate waterlogging. 

The right amount of water and a tree-friendly method are important for proper watering in summer.

The right amount of water

The water requirements of trees vary greatly depending on the tree species, age and location. The following rule of thumb is helpful:

During the growth phase, an average tree needs around two waterings, each with 150 to 200 liters of water per week. If it is very dry and hot, you can further increase the amount of water per watering. This makes more sense than watering another day.

Here's another rule of thumb: the higher the temperatures, the greater the need for water.

Which casting method is best?

In summer, the soil can become extremely hard during dry spells. If you then apply a large amount of water all at once, the dry, hard soil can barely absorb it. Especially in summer, it's crucial that the water soaks into the soil very slowly, ideally drop by drop. Therefore, it's important that the water seeps into the ground as slowly as possible so that it can actually be absorbed. This is difficult to achieve with a watering can containing 150 to 200 liters per watering. 

A very effective tool for this are tree watering bags, which slowly release water using drip irrigation. They can be installed without much effort and can be filled with a garden hose in just a few minutes. They then release the water drop by drop into the ground over a period of 6-9 hours. This means there is no runoff and no rapid seepage through the root area.

The right time of day to water trees

In summer, it is important that you water the trees either early in the morning or late in the evening. Then the trees have the best chance of absorbing as much water as possible before it evaporates. If you use tree watering bags, the correct time of day is far less important because the bags minimize evaporation. However, we recommend filling the trees with watering bags in the morning or evening.

Watch for signs of drought stress

The typical signs of drought stress in summer are:

• Dried, drooping, curled, or folded leaves
• leaf wagging or trembling
• shedding of leaves
• shedding of branches
• Formation of excessively large and small fruits.

We should support our trees with watering at the latest when these signs appear. Here is a text on the topic drought stress in trees.

Additional support: Fertilizing

Besides sufficient water, trees also need nutrients in summer to grow healthily and build up reserves. In most cases, however, well-nourished soil is sufficient, so no additional fertilization is necessary. However, a light application of organic fertilizer can be beneficial, especially for young trees or nutrient-poor soils.

It's important to avoid fertilizers high in nitrogen, especially from midsummer onwards. Nitrogen can promote excessive shoot growth, which puts additional strain on the tree. Organic materials like compost or worm castings are suitable, as they improve the soil in the long term and release nutrients slowly. You can find more information on this topic in this article. Fertilizing trees in summer.

Here is a more detailed text on the subject Water trees.

And here you can find information about the other months:
Water trees in spring, Watering trees in autumn, Watering trees in winter.