USE OF PLASTICS IN ECOLOGICALLY SOUND VEGETABLE PRODUCTION IN THE OPEN

From the start of the fifties experiments with soil-mulch were set up both in the USA and in Europe, mainly with strawberries.
These experiments envisaged a slight forcing effect on the one hand, but also weed suppression and the protection of the fruits from smudging by soil on the other hand.

From 1986 onwards mulching was again taken up in the experimental programmes in Belgium and Germany ; mainly now, however, in the framework of the maximalization of the ecological way of growing vegetables.

Apart from the exclusion of herbicides, attention is now mainly being paid to the possibilities of using soil-mulch in minimizing the draining of fertilizers in the soil, especially of nitrates, thus preventing the eutrophication of the soil and the groundwater.
Furthermore, a growing system is aimed at, that is as closed as possible, the plants being fertilized by means of trickle irrigation under the soil-mulch depending on their development, and the drainwater being collected again and recycled.

For the time being the problem of the plastic waste is best solved by incineration.
We are looking forward to the generalized use of compostable biopolymers in the near future.

Direct plant covering (DC) in spring is a cheap forcing method with a bearing on the warmth and light sensitivity phases of the plant.

Under the maritime climatic conditions prevailing in Belgium the determining thermosensitive phase lasts until mid-April, when the average minimum temperature under the DC reaches 8.5 °C and the light intensity in the open has risen to 1 500 J/cm²/day on average.

VII International Symposium on Timing Field Production of Vegetables

F. BENOIT

https://doi.org/10.17660/ActaHortic.1994.371.30