Customer case

Braber Groenvoorziening optimizes soil structure with DCM VIVIMUS®

About this client

Name

Braber Groenvoorziening

Sector

Garden Care

Location

Renesse

Braber Groenvoorziening, based in Renesse, operates in the regions of Zeeland, South Holland and West Brabant. Project manager Erik Timmer: 'Faced with a dilemma during one of the projects, Braber Groenvoorziening contacted DCM and called on DCM's advice to achieve a good final result.’

The project

Erik Timmer, project manager for the Zeeland region at Braber Groenvoorziening, explains: ‘The customer asked us to lay turf (sod) over an area of 3,100 m2 around a large industrial building, located on the transhipment site Overslagterrein Verbrugge in Vlissingen, next to a producer of chemical fertilisers. The question was to use the existing soil, which had been there for years, because removing the soil would entail enormous costs. The project also had to be completed at short notice.’

Quite a challenge

However, the soil was of poor quality. ‘It was compacted and greasy and its colour and smell were not good,’ Erik says. ‘This could partly be explained by the fact that trucks come and go on this transhipment site, transporting all kinds of raw materials such as lime, chemical fertilisers and sulphates. The trucks regularly pass within a few metres of the lawn. There is always some dust from the raw materials being transported. This settles on the site, including on the lawn. The paths are covered in white dust and after a rain shower, all the rubbish runs off onto the lawn.’

A soil analysis and a plan for top layer improvement

As Braber Groenvoorziening could not guarantee good lawn growth with the existing soil, the company, assisted by DCM, decided to improve the soil. To improve the soil, a special plan was drawn up with DCM. First of all, a soil analysis was carried out. The DCM account manager visited the site and took a soil sample. ‘The results of the soil analysis confirmed our feeling: the soil was not in good condition. It turned out that the EC value and pH of the soil were high.’

DCM then created two mixtures based on the existing soil to test grass seed germination. The mixture that performed best consisted of the existing soil, DCM VIVIMUS® FOR HEATHER/RHODO (soil improver for heather, rhododendrons and call acid-loving plants), and some sand.

DCM VIVIMUS® FOR HEATHER/RHODO was used to enrich soil life, increase organic matter content, lower pH and improve soil structure. Coarse sand was applied to further lighten the top layer texture; the existing soil contained a lot of heavy clay, which drains poorly and does not allow nutrients to pass through to the grass plants.

The implementation

‘Based on this ‘recipe’, we were able to improve the top layer,’ project manager Erik explains. Just before laying the turf, the compacted soil was loosened up to a depth of one metre. Braber Groenvoorziening then incorporated the DCM products and sand into the top layer. ‘We used 120 m3 of DCM VIVIMUS® FOR HEATHER/RHODO and 120 m3 of coarse river sand. After levelling the improved top layer, the turf was laid.

“DCM carried out tests to obtain the appropriate mixture guaranteeing the best rooting of the lawn starting from the existing soil”

Braber Groenvoorziening has been monitoring the turf very closely since it was laid. The company saw that the sods took root well within a short period of time. ‘We maintain the lawn since it was installed and apply the fertilization scheme established by DCM. The maintenance contract is renewed every year,’ Erik continuous. ‘During the growing season we used to mow the lawn every week. Today, a robot lawn mower mows the lawn. But we are regularly on site for other maintenance works and for monitoring. Every spring, we take a soil sample that we send to Fertilab. It is the DCM account manager who formulates an advice based on the obtained analysis results.’

A constant process

Twee jaar verder, ziet Braber Groenvoorziening dat de slechte grond weer wat naar boven komt. ‘Hierdoor verslibt de grond weer wat. Het bodemleven en het gras hebben het zwaar door de locatie-omstandigheden, waarin allerlei stoffen neerdalen op het gazon en in de bodem terechtkomen.’ Het bedrijf werkt hard om de groeicondities goed te houden ‘We blijven optimaal de organische meststoffen van DCM toepassen. Gezien de zware omstandigheden voor het bodemleven en de grasplanten zijn organische meststoffen de enige oplossing. We moeten op deze locatie zuinig zijn op het zorgvuldig opgebouwde bodemleven. Kunstmest zou hier alles kapot maken.’

Nog altijd tevreden klant

Two years later, Braber Groenvoorziening notices that the ‘bad’ soil is appearing again. ‘'This causes the soil to silt up a little bit again. The soil life and the grass are having a hard time due to the conditions on site, where all kinds of substances settle on the lawn and end up in the soil.’ The company works hard to ensure good growing conditions. 'We continue to optimally apply DCM's organic fertilisers. Given the difficult conditions for soil life and grass plants, organic fertilisers are the only solution. We have to take good care of the carefully constructed soil life. Chemical fertilizers would destroy everything here.’