Advice

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

In professional tree nurseries, well-planned basic fertilisation through the soil remains the foundation for producing strong crops. Nevertheless, foliar feeding is gaining importance as a targeted supplement: to make quick adjustments, mitigate stress, and refine plant quality.

When applied correctly, foliar feeding becomes a powerful finishing tool within a fertilisation strategy. It can visibly contribute to better growth, more intense colours, and greater resilience to abiotic stress factors through improved nutrient uptake. By applying the following seven practical success 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 far 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.

That is why it is essential to regularly check both the pH and hardness of your spray water. This can decisively affect application efficiency, particularly for trace elements such as iron.

2. Timing determines results

Applying foliar fertiliser “whenever convenient” often reduces effectiveness. Spray timing has a direct and significant impact on nutrient uptake efficiency.

The best results are generally achieved.

The best results are generally achieved:

early in the morning
late in the evening
at moderate temperatures
when the leaves are in an active growth phase

During these periods, stomata are open, allowing the plants to absorb nutrients more quickly. Avoid spraying during heat, intense sunlight, or just before rainfall. At high temperatures, the spray solution can evaporate too quickly, while rain may wash nutrients off the leaves before they are absorbed.

3. Not all leaves absorb equally

The uptake of foliar fertiliser varies greatly depending on leaf age and growth stage. Young leaves generally absorb nutrients more quickly than older leaves, which tend to have a thicker with a thicker wax layer. Foliar fertiliser is most effective when there is a sufficient amount of young, actively growing foliage present.

The growth stage also influences the effect:

During the build-up phase, foliar feeding acts as a fast and efficient growth stimulant, supporting young plants and allowing for quick adjustments.
Towards the end of the growing season, foliar feeding can be used to correct deficiencies and make targeted adjustments to enhance colour or provide an additional quality boost.
Under suboptimal soil conditions, such as low temperatures or excessive moisture, plants may struggle to absorb nutrients through their roots. In these cases, foliar feeding can meet specific nutrient demands independently of soil conditions.

This is how DCM OLEGA® COMPLEX effectively responds to the different growth stages

4. 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 highly depends on soil temperature, moisture levels, and root activity. In contrast, nutrients applied through the leaves are absorbed much more quickly.

For example, in cases of chlorosis or iron deficiency, a targeted foliar application can deliver faster visible results. Additional foliar feeding can also help restore plant growth when crops show general slowdown or colour issues.

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 basic fertilization. Instead, they serve to optimise it as part of a well-balanced fertilisation strategy, acting as an effective finishing tool.

5. Mixing without surprises

Much of the gain—or loss—occurs in the spray tank. Always check product compatibility beforehand and follow the correct mixing order, concentration, and recommended dosages.

Some practical points to consider:

Enkele praktische aandachtspunten:

mix products in the recommended order
use sufficient water
respect the correct product concentration
when in doubt, perform 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

For new combinations, always carry out a simple compatibility test first.

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

2. Leave to stand for 10 minutes.

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

Any doubts? Consult a DCM expert for product advice.

6. Leaf coverage matters more than spray volume

With foliar feeding, it’s not about “more is better,” but about achieving the most efficient leaf coverage possible. The goal is uniform distribution, maximum contact with the leaf surface, and “just enough” up to the point of runoff.

Too little liquid results in insufficient coverage and limited uptake, while excessive volume increases the risk of losses and inefficiency. The right droplet size combined with sufficient coverage makes all the difference.

7. Foliar feeding as a strategic optimisation

Optimising crop fertilisation is an ongoing process. Growing conditions are constantly changing, weather patterns are becoming more extreme, and quality standards for uniformity continue to rise. As a result, foliar feeding is increasingly used as a standard complement to basic fertilisation.

Not only to quickly correct deficiencies, but also to optimise growth, colour and root activity. Foliar feeding thus becomes a reliable component in achieving stable and predictable crop results.

With a well-considered approach, foliar feeding can serve as an efficient and consistent complement to basic fertilisation, with a visible impact on quality and uniformity.

Brief Summary

Foliar feeding is a targeted supplement to basic fertilisation, used to adjust growth, colour and uniformity. It serves as an efficient optimisation tool within your overall fertilisation strategy.

By applying it at the right time and during specific growth stages, you can significantly increase nutrient utpake, turning foliar feeding into a powerful finishing tool.

The timing of application, uniform leaf coverage, water quality, and tank mix all play a crucial role in the final result. Proper application delivers a stable and predictable result with a visible impact on plant quality.