Growbag COCO: Bell pepper production scales up with coir substrate

Dutch pepper grower Vink Sion is adding coir mats to their cultivation practices, taking a significant step towards making its operation more sustainable and optimizing its operations.

The company operates 364,000 square yards of glasshouses, producing around 250,000 plants per crop and over 20 million peppers per year. Last season, they grew their crops on the Growbag COCO from Klasmann-Deilmann for the first time. The experience has been so positive that the company will also switch a second greenhouse to this coir slab next season.

"We originally grew on rockwool. Last year, with a high plant density, we noticed that cultivation was becoming somewhat more difficult," said Cultivation manager Albert van der Ziel. "That's why we decided to use the coir slab in one of our three greenhouses, each covering an area of nearly 10 acres."

The choice fell on Klasmann-Deilmann’s Growbag COCO. According to van der Ziel, the mat fit their needs perfectly, and roots reacted positively.

"At first, the plants were still a bit wobbly compared to the rockwool mats, but the roots simply needed a little more time to establish themselves properly," he added.

Klasmann-Deilmann coir promotes crop growth and plant resilience

The first few months of the season immediately showed a clear difference compared to rockwool. The grower said the crop developed very vigorously, but that strong vigor resulted in somewhat slower fruit set, prompting an adjustment to the cultivation strategy.

"You realize then that you really have to take a different approach. We switched to a more generative cultivation approach, with cooler nights and warmer days. The close coordination with our crop advisor was very helpful in this regard," Van der Ziel explained. 

Vink Sion has now observed that the plants grown on the organic coir substrate are stronger and more robust, with consistently good fruit set and uniform growth. Production figures are also encouraging.

"At present, the yield of peppers per square meter on coir slabs is ahead of that of rockwool cultivation. It is still too early for definitive conclusions, but the outlook is promising," said the executive.

Vink Sion also observes differences in nutrition and plant resilience. The grower opted to use the mats without pre-made drainage holes and to cut these themselves later, which they say was more involved as it also required a different fertilization strategy, but the adjustments paid off in the end.

Making the right decisions faster

In addition to the substrate, data also plays an important role in the cultivation strategy. That is why Vink Sion works with Log & Solve sensors.

"We already had moisture meters ourselves, but Log & Solve sensors give us a much more complete picture," Van der Ziel explained. "This allows you to monitor what is happening in the root zone much more accurately"

"I love growth. I think that’s one of the most important characteristics of a strong crop," Van der Ziel said. "If you have a vigorous crop, it’s easier to produce peppers. On coir substrates, the crop continues to grow well, the roots develop excellently, and we see no signs of stress. Moreover, the fruit set remains well balanced. We’re very pleased with that."

That is why Vink Sion has decided to set up a second greenhouse using Growbag COCO from Klasmann-Deilmann next season. It’s a choice that underscores their confidence in this organic grow bag's performance.

*All images courtesy of Klasmann-Deilmann. 

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