Deckers Champignon lies close to the Dutch border in the German Geldern-Pont. In 1974, Hans Deckers started a small mushroom growing farm comprising four growing rooms where the mushrooms were still grown in trays. Now, thirty years later, the company has turned into one of the most modern manually harvesting companies in the region with a growing surface area of 13,000 m2. This makes it the largest company of its kind in Rheinland. On the 12th of June, 2004, a well-attended open day was held following the Dutch Mushroom Days.

The farm grows both white and chestnut mushrooms. In the existing company 800 m2 is filled with compost for white mushrooms and 400 m2 for chestnut mushrooms each week.  A new farm was recently opened with five rooms each of 1300 m2. Hans and son Marco, supported by manager Jan van Bergen, run the business.

Many will now be thinking: ‘hang on, rooms of 1300 m2, that can't possibly all be picked by hand?’. But that's where you're wrong, together with AdVisie one of the clear goals during the design phase for the new facility was lowering general overheads and picking costs while creating the right conditions for year-round harvest of quality mushrooms with a long shelf life - all view in of the current and future competitive position of hand picked mushrooms.

Buildings and equipment

The size of the rooms helped lower general costs and the rooms have been equipped to create optimal picking conditions. Each room has four rows of shelving , six beds high. The lowest bed has been installed 25 centimetres higher than usual, while the 1.20 meter wide beds are narrower than standard beds. This allows the pickers to work with better posture - and an accordingly better performance. The pickers harvest from self-propelled hydraulic picking platforms. This piece of equipment also contributes to increased picking performance and by using the selective method of continually picking, the quality of the mushrooms is better

The climate installation has extra large heating and cooling blocks. This means the climate units can work with lower heating water temperatures, creating a more stable and improved growing room climate.

Innovations are also apparent in the condenser. Cooling the condenser is namely based on the principle of evaporative cooling. The water used is the condensation water from the evaporators, topped up if necessary by well water.

The big advantage of this system is that growers can utilises the full cooling capacity in the summer when it is most needed. This contrary to air-cooled condensers, which are often unable to exhaust enough heat from the growing room in hot weather causing the available cooling capacity to drop - just when it's really essential. Another advantage is that all the water evaporates so none has to be drained away.

The existing farm was built from sandwich panels - which had excellent insulation properties. For the new buildings aerated concrete walls were a conscious decision. The buffer effect of aerated concrete creates a more constant and stable climate - all good for mushroom quality.

Quality and marketing

All the mushrooms are sold via Rheinland Champignons, an association of German growers. As the contact with the buyers is direct and the perishable nature of mushrooms a fact of daily life, the importance of quality is never underestimated. 

Deckers strongly believes that responsibility for mushroom quality from compost to consumer is the grower's. He is frustrated by other growers whose attitude is ‘once the mushrooms have left the farm, it's no longer my concern’, as far as Deckers is concerned there's no future for this type of mentality. He utterly fails to understand how certain growers and traders have the nerve to supply so-called premium quality mushrooms that don't even deserve to be labelled as 2nd quality. As is clear by now, quality is the main priority at this company. Cultivation and picking are concentrated on quality and long storage life - aspects considered far more important than squeezing out another kilo of production.

Regarding commercial activities, the company is clearly driven by market demands. Not just producing to produce, but only growing the things the market wants. Failure to do so simply reduces your own prices, sets a low price limit for the coming period and all without any guarantee that higher volumes will be ultimately sold. If there's no call for e.g. giant flats - well don't grow them. Picking on a 7-day -a week basis is also necessary to optimally serve the market.

The environment

The environment is also a major consideration at Deckers. On the farms there is absolute zero tolerance of chemical pesticides and formalin. The mushrooms are grown on “bio” casing soil - untreated with formalin. The operational management system concentrates on preventive measures aimed at keeping disease vectors at bay.

All containers and packaging material entering the farm is cooked out in a specially designated area, bearing in mind that containers are one of biggest infection sources of dry and wet bulb. Flies, another potential disease transmitter, stand little chance on the farm; before they can even start causing any damage they are trapped using fly traps, strips and lamps. Infections rarely rear their head on the company.

Waste disposal has not been ignored either; all waste water from the new farm will be purified using a helophyte filter system. The purified water can then be used for cleaning.

Cultivation and quality

In cooperation with AdVisie a philosophy has been developed that a mushroom must only absorb water with nutrients from the compost, this results in a less perishable mushroom.  If too much water is absorbed from the casing soil, the mushroom is simply soaking up ‘nutrient -poor’ water. This type of mushroom is far more perishable. A certain level of compost activity in the beds is a pre-condition to ensure a constant flow of nutrients from the compost to the mushrooms - 90 kilogram compost per m2 is the minimum requirement. In addition, from the pinheading stage, the maximum possible ventilation is aimed for with the fan in the lowest possible position.

During and immediately after filling as much water is given as the compost can take. It’s essential that compost quality is excellent. Water is subsequently only given in tiny amounts to maintain the casing soil condition. Hardly any water is sprayed on the actual mushrooms.

CO₂-shot is also resorted to as little as possible, this treatment has a negative effect on the shelf life of mushrooms. Calcium chloride is the preferred way to regulate heading. The salt is sprayed in the preparatory phase. Calcium chloride is also dosed in the first and second flush to improve the firmness and storage life of the fruits.

Two flushes are picked in a five-week schedule. Experience showed that the quality of the third flush was inconsistent and often disappointing. On the bed the mushrooms may seem OK, but once they reach the trading stage the quality was often inferior. They discoloured too quickly. If a grower wants to fully endorse the quality of his produce than only the best will do, reason enough for Deckers to leave the third flush for what it is.

Pictures of the Deckers farm can be found in our In Pictures section >