Emsland Gemuse is a special greenhouse. It is part of the Emsflower garden centre, and in winter the greenhouse is filled with bedding plants. In summer, the greenhouse holds tomatoes and peppers. The choice of substrate is equally special. “As a general rule, we do not work on rockwool,” says production manager Peters, “mostly for environmental reasons." Emsland Gemuse’s produce finds its way to regional markets, and the environment is important in Germany.
Grow bagsThe grow bags are filled with a mix of wood fibres from the German company Kleeschulte and perlite from another German firm, Knauf. Dirk Muehlenweg of Knauf is one of the developers of the product. He saw opportunities for perlite in vegetable cultivation and went to work with it. A mix of coir brought good results, but the coir blend also has its drawbacks. "In some cases, coir lacks constant quality, and the environmental consequences for producing countries aren’t always that good. ," he says. "Fresh water is needed to wash and buffer the product, taking a heavy toll on fresh water supply. That is not a sustainable process in our opinon. That is why we started to look at a different product"
This resulted into the option for Kleeschulte wood fibres. The regionally produced Topora fibres are mixed with perlite, an amorphous volcanic glass that has a relatively high water content. "The sterile perlite, provided by Knauf, makes up the frame, the wood is the buffer and gives room to the bacteria and the soil," says Christophe Stegemann of Kleeschulte. The soil is an important feature of the natural substrate, as is the option for steaming the substrate after cultivation and reusing it in additional cultivation. "You can’t even call it recycling,” says Muehlenweg. “It’s a matter of continuous use.”
Over 3 hectaresIt’s the third season Emsland Gemuse is using the Grow Bags. "The first year we had two rows, and now we have over 3 hectares," says Peters. "3 hectares of tomatoes, and the total mini cucumber acreage." Tomato plants are grown on Grow Bags Medium, with perlite of 0-3 millimetres. For growing cucumbers, Grow Bags Coarse is used with perlite of 2-6 mm. These are also suitable for peppers.
So how are the crops doing? "They look good,” says Peters. “The mat drains easily, making the formation of the fruit in spring and autumn all the more easy. In spring it’s more generative, in the autumn it’s slightly drier. It is a porous substrate, which is positive for the amount of oxygen that reaches the roots.”
The acreage containing Kleeschulte Grow Bags will be expanded again next year. Natural substrates are said to produce stronger plants than rockwool. Peters is careful in jumping to conclusions. "I think there are many factors involved,” he concludes. “Insects, pests, all of these can be a nuisance.”
For more information:
Christoph Stegemann (e-mail)
T: +49 152 22 61 83 67+49 152 22 61 83 67
Dirk Muehlenweg (e-mail)