CUT-ROSE PRODUCTION IN CLOSED SYSTEMS WITH EMPHASIS ON ENVIRONMENTAL ASPECTS

Article number

303_2

Pages

15 – 22

Language

Abstract

Before the year 2000, the Dutch greenhouse industry want’s to have changed to the use of production systems with minimal consumption of non-renewable natural resources and minimal emission of polluting matters.
This will force the growers to use recirculating watering systems, to invest in long-life and recyclable system materials and to be responsible for the organic waste materials.
Production separated from the greenhouse soil is considered to be the answer to the demand for these production systems with minimal environmental load.

Many growers started to use artificial substrates such as rockwool, which requires a non-renewable natural resource but has the advantage that it can be recycled.
This production method opens in principle the possibilities for recirculation, since the rockwool slabs are usually placed on plastic or metal gutters to separate the slab from the subsoil to prevent transfer of diseases.
These gutters can be easily used to collect the excess nutrient solution coming from the slabs which was given to the plants to equalize differences in water consumption and to prevent excessive salt concentrations.
The use of recirculation in such systems however stagnates because of expected problems with spread of diseases, build-up of elements in the solution and because of a negative economic feasibility.

A new system was designed to overcome the problems mentioned above.
The program of demands for this system contained some starting-points that were tested in a comparison with a standard production system.
These starting-points were:

Increase of production through the use of rolling benches.
Minimal problems with elements building up through the use of a watering system capable to rinse the substrate.
Avoid root disease problems through the use of substrate with 10% air volume in saturated conditions.
System materials may not cause new environmental load problems.
Non-recyclable plastics or growing media cannot be used.
Avoid or limit the use of materials that require non-renewable natural resources.
All systems materials should have a long life expectation through a good design and the use of proper materials.
The system should be easy to clean and allow steam sterilization.
A rose crop should remain on the system for a production period of at least four years.