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'Naturally Stronger': no judgement on chemicals, but emphasis on healthy cultivation methods

Not rules, but natural cycles are the guiding principle for the Naturally Stronger label


The Naturally Stronger label is an initiative of three growers. They grow without chemical pesticides and artificial fertiliser. The difference with organic quality marks such as Skal is that there is no need to apply for an exemption if there is unexpectedly no organic starting material available. Natuurlijk Sterker comes from an inner motivation to grow as naturally as possible, not to follow rules,' says one of the initiators, Johan Vreugdenhil.

Nursery Vreugdenhil-Mooimakers is an 8-hectare nursery with a garden centre and planting service in Eldersloo. Vreugdenhil supplies the entire market, from consumer to exporter and everything in between. Since 2014, the nursery has operated without chemicals and artificial fertiliser. In 2018, the label Natuurlijk Sterker was created, founded by Vreugdenhil-Mooimakers together with Decohof Nursery in Overgoor and Boomkwekerij H. Veldhuis in Dalfsen.

Working method

Johan Vreugdenhil explains: The natural cycles are leading in cultivation under this label. The plants grown under the Naturally Stronger label come from healthy, disease-resistant soil. They have a strong and extensive root system with soil life. This makes these plants more successful than plants which have not been cultivated in a natural way. The leaves are thicker, greener and firmer, which provides resistance to diseases and pests and other external stresses.' He continues: The plants are placed further apart so that the wind and cold can get around them well. This way, the plants make themselves strong in a natural way. In the nursery, they also have to deal with pests and diseases, so they develop natural defences.

Naturally Stronger makes use of undergrowth, such as herbaceous plants. Raw materials are also used in a circular way by making use of organic residual flows such as leaves, wood and grass clippings. Processed materials are used as compost, mulch and fertiliser. Naturally Stronger certified growers use no chemical pesticides or artificial fertiliser and have their cultivation inspected once a year by an independent lab. Companies that are Skal-certified also meet the membership requirements for Naturally Stronger.


'We grow organically, but it is not called that because the cultivation is not Skal-certified'.


Organic, but not official

Vreugdenhil is very positive about the Skal label and also praises Skal's objectives. Nevertheless, he and the two other initiators wanted to give their label a slightly different look. The difference between the organic Skal label and the Naturally Stronger label is that for the latter, no exemption is requested for starting material.

Sometimes, as a grower, you cannot avoid buying a cutting that has not been cultivated organically, because organic starting material is scarce for some product groups. Then I don't have to apply for a special exemption for that product group and I can just start working with that starting material. You can do that under the Skal label too, but you have to pay for it first.
Vreugdenhil summarises: 'Naturally Stronger does not want to increase costs. If you farm under the Naturally Stronger label, you do not compromise on the Skal rules, but you do not have to pay for exemptions. So we grow organic, but we are not allowed to call it that because the cultivation is not Skal-certified.

Incidentally, as a Naturally Stronger certified company you can also be Skal certified. But even then we pretend to be unique, because Natural Stronger says much more about the added value of the product than the certificate "organic". "Organic' actually only means that your product is inspected. It indicates what the breeder is not allowed to do. Naturally Stronger does not proclaim that chemistry is bad for nature, but explains as much as possible about a healthy and natural way of growing, which is beneficial for plants. By placing as little emphasis as possible on rules, the label tries to give a stage to the inner motivation of the grower.


Another difference with Skal is that the Naturally Stronger label is only valid when the entire company is cultivated in the required manner. When a few product groups are not cultivated in a natural way, the certification expires. Naturally Stronger is a company vision. Otherwise it will not work. That is another proof that the motivation for natural breeding comes from us, not from the market.

Mix of organic fertilisers and fungi
Johan Vreugdenhil grows in the open air and also in pots. Then you need a bit more fertilisation than just organic manure. We don't use artificial fertiliser, but we do use soil improvers and organic fertilisers. Initially, we only used animal organic fertiliser, but in spring it took too long for it to take effect. Now we work with Plant Health Cure's vegetable fertiliser OPF granules, which is released at low temperatures. We are now looking for a combination of animal and vegetable fertilisers, because animal fertilisers also stimulate part of the growth chain. They complement each other. We also apply various soil improvers, rhizosphere products and mycorrhizae from this supplier in the potting soil that we compile and mix ourselves. These are in line with the natural environment of the plant, in order to rebuild soil life in places where it had once broken down. We also work with EcoStyle products.

'Naturally Stronger is a corporate vision'.


Stefan Even, cultivation adviser for tree nurseries at Plant Health Cure, explains more about the effect of a natural soil on the plant. As a producer and supplier of soil improvers, vegetable fertilisers, rhizosphere bacteria, mycorrhizae and plant reinforcers, we visit many growers and assist them in their greening and cultivation optimisation. The starting point here is: working from soil and plant resilience, with the aim of growing a naturally strong plant. A resilient soil is characterised by a good structure, sufficient nutrients and good soil life, including the right bacteria, fungi and worms. The right balance is needed for a resilient soil. The soil bacteria ensure the release and conversion of minerals into nutrients that can be absorbed by the plant. In addition, the rhizosphere bacteria and fungi provide protection against external attackers.

This natural protection of the root is an indispensable link in a resilient soil. The mycorrhizal fungi increase the absorption capacity for water and minerals by up to 700 percent. As a result, the reach of the roots is many times greater and water and nutrients located further from the root are handled more efficiently. As a result, the plant will experience less stress and be less sensitive to drought and nutrient deficiencies in the immediate vicinity of the roots. In cultivation, we see that the application of mycorrhizae visibly increases root intensity. But at least as important is the fact that the chances of attack and survival of the plant in the supply chain are strongly increased, so that over-nutrition is reduced to a minimum.


According to Even, the limited absorption capacity of the (transplanted) plant, combined with poor rootability and a lack of soil biology, often leads to problems with fouling and road growth: 'Proper plant preparation, where the right biology is introduced into the root environment, is crucial for good road growth. By adding mycorrhiza products at planting, the attack of the plant is strongly promoted and drop-outs reduced. This, of course, makes the plant stronger.

Although according to Vreugdenhil the Naturally Stronger growers are primarily motivated internally and not by the market, Vreugdenhil can easily keep up with the trade. There are probably enough growers with a lower cost price, but perhaps they are in a different market. That also makes a difference. In the end we just supply part of the regular market.

Investing in the future
All in all, the grower is more concerned with his working method than with the pecuniary gains. With hindsight, you may realise that you could have earned more in other ways. But I bet on this working method and wouldn't have wanted it any other way. Apart from that, it was a long-term investment. I expect Natuurlijk Sterker to earn more in the future and to make a difference with this label.