Advice

Foliar feeding in tree nurseries: 7 success factors for improved yield and plant quality

In professional tree nurseries, well-designed soil-applied base fertilisation remains the foundation for producing strong crops. However, foliar feeding is becoming increasingly important as a targeted supplement: to make rapid corrections, help plants cope with stress or fine-tune plant quality.

When applied correctly, foliar feeding becomes a true finishing tool within a fertilisation programme. It can visibly contribute to better growth, more intense colour, and greater resilience to abiotic stress factors through improved nutrient uptake. By applying the following seven practical factors, you can successfully integrate foliar feeding into your nursery operations.

1. Start with the basics: water is more than just a carrier

A foliar fertiliser only performs optimally when nutrients are truly available for uptake through the leaves. Water quality plays a much greater role in this process than is often assumed. A pH that is too high or excessive water hardness can cause nutrients to precipitate or become less available for uptake.

For this reason, the pH and hardness of irrigation or spray water should be checked regularly. This is particularly important for micronutrients such as iron, where water quality can have a significant impact on application performance.

2. Timing determines effectiveness

Applying foliar fertiliser "whenever it is convenient” often reduces effectiveness. The timing of an application has a direct and significant impact on nutrient uptake efficiency.

Good results are generally achieved.

early in the morning
late in the evening
at moderate temperatures
- when leaves are actively growing

During these periods, the stomata are open, allowing plants to absorb nutrients more quickly. Avoid spraying during hot weather, intense sunlight or just before rainfall. At high temperatures, the spray solution dries out too quickly, while rain may wash away nutrients before they can be absorbed.

3. Not every leave absorbs nutrients equally

Foliar nutrient uptake varies considerably depending on leaf age and growth stage. Young leaves generally absorb nutrients more quickly than older leaves with a thicker waxy layer. Foliar fertiliser is more effective when sufficient young, actively growing foliage is present.

However, the growth stage also determines the effect:

During the development stage, foliar feeding provides targeted growth stimulation and allows young plants to be fine-tuned where needed.
Towards the end of the growing season, foliar feeding can be used to correct deficiencies and make targeted adjustments for better colour or an additional boost in quality.
Are plants having difficulty absorbing nutrients from the soil, for example due to cold conditions or high humidity? In such situations, foliar feeding can help meet specific nutrient needs independently of soil conditions.

This is how DCM OLEGA® COMPLEX responds specifically to the needs of plants at different growth stages

4. Nutrient deficiencies ? Acting quickly pays off.

When a crop shows signs of nutrient deficiency, rapid intervention is essential.

Nutrient uptake through the roots takes time and is highly dependent on soil temperature, moisture levels and root activity. Nutrients applied through the leaves can be absorbed more quickly.

In the case of chlorosis or iron deficiency, for example, a targeted foliar application can produce visible results more quickly. In cases of general growth delays or colour problems, supplementary foliar feeding can also help get plants growing again.

It is important to note that foliar fertilisers such as DCM OLEGA® COMPLEX, DCM LEAFGEL® NK, DCM OLEGA® FER and DCM OLEGA® CALCIUM do not replace base fertilisation. Instead, they complement and optimise it as a finishing tool.

5. Mixing without surprises

A lot can be gained, or lost, in the spray tank. Always check product compatibility beforehand. Follow the recommended mixing order, concentrations and application rates.

A few practical points to keep in mind:

mix products in the recommended order
use sufficient water
respect the correct product concentrations
if in doubt, carry out a compatibility test first

Using too little water can reduce uniform uptake and increase the risk of residues on the leaves.

The 10-minute pre-spray check

When using new combinations, first carry out a simple compatibility test.

1. Mix the fertilisers and water in the correct proportions in a transparent container.

2. Leave the mixture to stand for 10 minutes.

3. Check for signs of incompatibility, such as precipitation, separation or foaming.

In doubt? Ask a DCM expert for product advice.

6. Leaf coverage matters more than spray volume

With foliar feeding, the aim is not simply “the more, the better,” but to achieve the most efficient leaf coverage possible. The goal is uniform distribution, maximum contact with the leaf surface and “just enough” spray solution up to the point of run-off.

Too little spray solution results in insufficient coverage and limited uptake, while excessive volumes increase the risk of losses and inefficiency. The right droplet size and sufficient coverage make all the difference.

7. Foliar feeding as a strategic optimisation tool

Optimising fertilisation in your crops is an ongoing process. Growing conditions change, weather patterns are becoming more extreme, and expectations for uniform quality are high. For this reason, foliar feeding is increasingly becoming a standard complement to base fertilisation.

Not only to quickly correct deficiencies, but also to optimise growth, colour and root activity. In this way, foliar feeding becomes a valuable part of a well-considered crop strategy.

With a well-considered approach, foliar feeding can provide a reliable and efficient complement to base fertilisation, with visible effects on crop quality and uniformity.

Brief Summary

Foliar feeding is a targeted supplement to base fertilisation, allowing growers to fine-tune growth, colour and crop uniformity. It serves as an effective optimisation tool within a fertilisation strategy.

By targeting the right timing and specific growth stages, nutrient uptake can be significantly improved, turning foliar feeding into a highly effective finishing tool..

The timing of application, uniform leaf coverage, water quality and tank-mix compatibility jointly determine the final result. Correct application can provide more stable and predictable results, with visible effects on plant quality.