Natural Amino Acids Give Bellflowers Stronger Roots
New trials from AU FOOD show how natural substances can improve rooting and produce healthier cuttings – completely without the use of synthetic hormones.
Rooting is absolutely crucial in all cutting propagation. Without roots – no plant. But not all varieties root equally easily, which can be costly for nurseries in the form of waste, empty pots, and lost production time. At Aarhus University’s Department of Food Science (AU FOOD), researchers have now tested whether natural amino acids can help bellflower (Campanula) cuttings develop stronger and more reliable root systems. The results are promising – especially for varieties that otherwise struggle to root.
Two popular varieties were tested in the trial: Deep Blue Ocean (blue flowers) and White Ocean (white flowers). One variety rooted quickly and effectively – the other lagged significantly behind. After 21 days, all Deep Blue Ocean cuttings had developed roots, while only 25% of the White Ocean cuttings had done the same.
The researchers then wanted to investigate whether natural amino acids could improve rooting – and chose to do so in a hydroponic system, a soil-free cultivation system where roots grow directly in nutrient-rich water, allowing precise measurement of both environment and results. This proved to be an effective method for both testing and documenting the effect.
📈 The results speak for themselves:
-
In White Ocean, the percentage of rooted cuttings increased from 25% to 45%.
-
In Deep Blue Ocean, the root systems became both longer and stronger, even though all cuttings had already rooted.
At the same time, the trial provides valuable insight for nurseries:
-
The ability to form roots varies greatly between varieties – this should be examined before starting new production.
-
Natural amino acids can be a useful tool to improve root development – especially when working with weakly rooting varieties.
-
Since synthetic rooting hormones are not permitted in Danish horticultural production, it is a major advantage to use organically based substrates enriched with natural, well-documented additives.
By using this method, growers can achieve more uniform results, less waste, and higher quality in their cutting production – in a way that is both practical and sustainable.
🔬 About the project
The project was carried out at Aarhus University, Department of Food Science (AU FOOD), in collaboration with HortiAdvice. Plant material and photos were kindly provided by Thoruplund A/S (Jan Uglebjerg Storm and Jacob Morten Andersen). The trial is part of the GUDP project FUTFLOR, which focuses on the sustainable flower production of the future.
Scientific Declaration & Contact Information
CONTENT & PURPOSE | |
Study type | Using controlled hydroponic experiments, researchers tested how natural amino acids influence rooting in Campanula cuttings. The study compared two popular varieties with different rooting capacities and measured both rooting success and root growth, as well as additional physiological and biochemical traits. By working in a soil-free system, the researchers could monitor the environment precisely and document the effect of amino acid application in detail. The aim was to understand how external, naturally based compounds — permitted in Danish nursery production — can be used to improve rooting and strengthen cuttings. |
External partners | Thoruplund A/S, HortiAdvice |
External funding | This project was carried out at Aarhus University, Department of Food Science (AU FOOD), in collaboration with HortiAdvice. Plant material was kindly provided by Thoruplund A/S. The experiment is part of the GUDP project FUTFLOR. |
Potential conflicts of interest | The project was carried out in collaboration with HortiAdvice and Thoruplund A/S. No conflicts of interest are declared. |
Contact information | Ivan A. Paponov Kimie Kongsøre |