Trees fertilize themselves in the cycle of the seasons.

Table of Contents

• The natural nutrient cycle in the soil
• Fertilizing and watering: Supplying the tree with nutrients and water
• Spring: Start of a new growth phase
• Summer: Growth and reserves are built up
• Autumn: Integration of growth and preparation for winter dormancy
• Winter: Trees in their dormant phase
• The tree bath worm compost tree fertilizer
• Common mistakes when fertilizing trees

Trees are strongly influenced by the cycle of the seasons. Within a year, trees go through different phases of growth, integration, and dormancy. Their nutrient requirements change accordingly.

This article explains the role of tree fertilization in different seasons and what you should pay particular attention to in each season. You can find basic information on this topic in the article [link to article]. How do you properly fertilize trees?

The natural nutrient cycle in the soil

Forests have a stable nutrient cycle: Fallen leaves and other organic material are decomposed by microorganisms. This process releases nutrients that are then available to the trees. Furthermore, the forest floor is inhabited by a diverse range of soil organisms. However, in many gardens, and especially in cities, this cycle is restricted. Leaves are often removed, soils are compacted, and soil life is greatly reduced.

When considering fertilization, we recommend also thinking about soil care. Organic materials such as compost, mulch, or worm tea not only improve nutrient supply in the long term but also promote soil life. Therefore, we generally recommend using organic materials. 

Fertilizing and watering: Supplying the tree with nutrients and water

Nutrients and water are equally essential for a tree's health and growth. If a tree shows deficiency symptoms, it could be due to either a nutrient or water deficiency; the tree often exhibits the same symptoms. Therefore, if you notice deficiency symptoms, we recommend first checking whether the tree might be getting too little water. 

Furthermore, water is essential for trees to absorb and metabolize nutrients in the soil. When considering fertilizing trees, we recommend always thinking about watering as well. This is especially important during dry periods. Therefore, you will find specific watering tips in the sections for each season.
And now to the seasons:

Spring: Start of a new growth phase

Spring is the most important time for fertilizing trees. With rising temperatures, a new growing season begins: buds open, new leaves emerge, and the trees begin to blossom. At the same time, the trees develop... Their root system also expands. During this phase, their nutrient requirements increase significantly. Nitrogen plays a particularly important role, as it supports the growth of leaves and shoots. 

Fertilizing is ideally done at the beginning of the growing season, usually between March and May. It's important to apply the fertilizer evenly around the roots and lightly work it into the soil. If the soil is already dry in spring, we recommend watering the tree regularly as well.
If the tree has sufficient nutrients and water available this spring, it can optimally prepare for the new growing season.

You can find more information in the article. Fertilize trees in spring and in the article Water trees in spring. 

Summer: Growth and reserves are built up

In summer, the leaves are fully developed and the trees use the abundant sunlight for photosynthesis. Now the trees produce a lot of energy, which they use for growth and as a reserve. The need for additional nutrients is usually lower during this phase than in spring. Most trees can obtain sufficient nutrients from healthy soil. Heavy fertilization is therefore often unnecessary in summer and can lead to undesirable growth, especially in late summer when nitrogen levels are high.

If the soil is nutrient-poor or if young trees are to grow particularly vigorously, a light application of fertilizer can be beneficial. Organic fertilizers are especially preferable in summer, as they have a slow-release effect and improve the soil in the long term. It is important to keep fertilization moderate and ensure good soil structure.

Trees need plenty of water to photosynthesize. Therefore, adequate water supply is especially important in summer. A layer of mulch can help retain moisture and support soil life.

You can find more information in the article. Fertilizing trees in summer and in the article Water trees in summer. 

Autumn: Integration of growth and preparation for winter dormancy

In autumn, most deciduous trees begin to change color and shed their leaves. At the same time, they store important reserves in their roots and trunks. Now, the focus is no longer on growth, but on preparing for winter dormancy. Therefore, heavy fertilization in autumn is generally not advisable.

Moderate fertilization with organic materials can help improve the soil and strengthen soil life. Materials such as compost, worm castings, or mulch are particularly suitable. These decompose slowly and contribute to long-term soil fertility. In autumn, you should avoid high nitrogen applications. Nitrogen would stimulate the growth of new shoots that wouldn't have enough time to mature before winter. 

You can find more information in the article. Fertilize trees in autumn and in the article Watering trees in autumn. 

Winter: Trees in their dormant phase

In winter, the metabolism of most trees is greatly reduced and growth is minimal. During this time, the roots absorb very few nutrients. Therefore, fertilization is generally neither necessary nor beneficial during the winter months.

Instead, winter offers a good opportunity to protect the soil and prepare it for the coming growing season. A mulch layer of leaves, compost, or bark can help protect the soil from extreme temperature fluctuations and promote soil life.

At the same time, organic material improves soil structure in the long term. As it decomposes over time, valuable nutrients are released that are available again in the spring.

You can find more information in the article. Fertilizing trees in winter and in the article Watering trees in winter. 

The tree bath worm compost tree fertilizer

The tree bath worm compost liquid fertilizer It provides trees with essential nutrients while simultaneously enriching the soil. Its composition allows for year-round use. Baumbad worm compost liquid fertilizer contains a wealth of living microorganisms, humic acids, plant-available nutrients, and growth-promoting enzymes. It is also suitable for use in tree watering bags.

Common mistakes when fertilizing trees

Similar mistakes are repeatedly made when fertilizing trees. These include:

• Excessive nitrogen application in summer
• Fertilizing dried-out soil
• Late nitrogen fertilization in autumn
• The belief that "more fertilizer helps more"

A balanced fertilization approach always takes into account the condition of the soil, the age of the tree, and the respective season.