Classifications

• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01G—HORTICULTURE; CULTIVATION OF VEGETABLES, FLOWERS, RICE, FRUIT, VINES, HOPS OR SEAWEED; FORESTRY; WATERING
  • A01G24/00—Growth substrates; Culture media; Apparatus or methods therefor
  • A01G24/10—Growth substrates; Culture media; Apparatus or methods therefor based on or containing inorganic material
  • A01G24/18—Growth substrates; Culture media; Apparatus or methods therefor based on or containing inorganic material containing inorganic fibres, e.g. mineral wool
• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01G—HORTICULTURE; CULTIVATION OF VEGETABLES, FLOWERS, RICE, FRUIT, VINES, HOPS OR SEAWEED; FORESTRY; WATERING
  • A01G24/00—Growth substrates; Culture media; Apparatus or methods therefor
  • A01G24/40—Growth substrates; Culture media; Apparatus or methods therefor characterised by their structure
  • A01G24/44—Growth substrates; Culture media; Apparatus or methods therefor characterised by their structure in block, mat or sheet form
• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01G—HORTICULTURE; CULTIVATION OF VEGETABLES, FLOWERS, RICE, FRUIT, VINES, HOPS OR SEAWEED; FORESTRY; WATERING
  • A01G24/00—Growth substrates; Culture media; Apparatus or methods therefor
  • A01G24/50—Growth substrates; Culture media; Apparatus or methods therefor contained within a flexible envelope

Definitions

• the invention relates to mineral wool substrates used for above-ground cultivation.
• mineral wool in particular rock wool (based on volcanic rocks or blast furnace slag) or glass wool for what is commonly called the above-ground culture 0 has experienced a great expansion in recent years.
• rock wool based on volcanic rocks or blast furnace slag
• glass wool for what is commonly called the above-ground culture 0 has experienced a great expansion in recent years.
• These products indeed have very interesting characteristics. They are relatively inexpensive, easy to implement and * offer for culture itself, interesting properties: safety for plants, sterilized medium, good water retention ...
• the mineral wool substrates used hitherto are products directly derived from those intended for thermal insulation. These are products in the form of felts, the fibers of which are maintained by ut) binder product based on resin. With respect to traditional insulation felts, the main difference
• the mode of production determines for an important part the structure of the felt.
• the fi ⁇ tres are made from fibers coming directly from the drawing from molten material. These fibers are transported by gas streams to a gas permeable receiving conveyor. On this conveyor the fibers are retained while the gases are evacuated.
• the felt is gradually formed by the accumulation of fibers on top of each other.
• the fibers are arranged in a privileged manner along planes parallel to the receiving conveyor. For felts intended for Insulation this arrangement is advantageous insofar as it corresponds to good thermal resistance.
• the "horizontal" arrangement of the fibers is found in the soilless growing substrates that have been proposed so far.
• the substrates are marketed and used in the form of "breads", that is to say parailissepilvesdiques blocks whose dimensions, and in particular the width, are determined by the cultivation techniques. Users want to be able to have breads whose width varies according to the case but can exceed 200 mm or even 300 mm. To obtain these dimensions on felts ordinarily conditioned to the dimensions of the insulation products, it has been the practice to cut the loaves so that the fibers during use are arranged substantially horizontally, that is to say ie approximately parallel to the ground or to the support on which the bread rests.
• cubes or clods intended for plant growth.
• the cubes are usually made of the same material as bread, but their dimensions are much smaller, they are of the order of 100 mm per side.
• the cubes are often prepared so that the fibers in the position of use lie in substantially vertical planes.
• the reason for this difference is also due to the packaging method of these cubes. These are obtained from felts cut first into transversa ⁇ bands and then these bands themselves cut in their width to the dimensions of the desired cubes.
• felts cut first into transversa ⁇ bands and then these bands themselves cut in their width to the dimensions of the desired cubes.
• the object of the invention is to provide a culture substrate in the form of breads, that is to say substrates on which the culture is completed, in contrast to the cubes used only for the growth of plants, substrate having new properties compared to those of traditional breads, properties which improve the conditions for plant growth.
• the breads according to the invention consist of mineral fiber felts and are characterized by the fact that the fibers are placed essentially in vertical planes in the position of use. It is remarkable, as will be seen in the examples, to note that this modification of arrangement results in a substantial improvement in crop yields. The reasons for this improvement are not yet fully understood. It is however possible to compare this result with the particularities observed in the "vertical" use of the fibers, in particular with regard to the water retention properties of these substrates.
• the fibers of which are arranged in vertical planes, it can be seen that the distribution of the solutions in the height of the substrate is much more homogeneous, and that in particular saturation is avoided even in the lowest parts.
• the crop breads according to the invention provide better drainage.
• This better control of the distribution of solutions does not only eliminate the risk of saturation, it also allows, for example, a good distribution of nutritive constituents and in particular avoids the accumulation of localized salts.
• the tests carried out also show that the roots develop and penetrate more easily from the cube into the bread. The reason for this better passage of the roots when the fibers of the bread are in vertical planes probably comes from the very texture of the felts which constitute them.
• the culture breads according to the invention also make it possible to minimize the difficulties encountered when the ground or the support on which the bread is placed is not perfectly horizontal.
• the use of traditional substrates with horizontal fibers requires a support which is also very horizontal, otherwise the solutions tend to saturate the lower parts, neglecting the upper parts, leading to a complete imbalance in the hydration of the plants.
• the substrates according to the invention are much less sensitive to these level variations.
• the mineral fiber substrates according to the invention are produced from felts obtained under usual conditions.
• the felts from which the loaves are cut have fibers in planes substantially parallel to the faces of the felts.
• the cutting of the felt is made so that the edges, or if the thickness is desired, become the upper and lower faces of the cultivation bread.
• felts are obtained by collecting fibers conveyed by a gas stream, on a conveyor serving as a filter. To facilitate the deposition of fibers and the elimination of carrier gases it is necessary to maintain an energetic suction under the conveyor. The energy required for this suction is all the more important as the gases have more difficulty in filtering through the conveyor and the mass of fibers already deposited. It is understood under these conditions that in order to be able to operate economically, it is necessary to limit the thickness of the felt being formed on the conveyor.
• the thickness is determined by compliance with very precise standards, felts more than 300 mm thick are not usually produced and the the most usual thicknesses are of the order of 75, 100 and 150 mm.
• the assembly of several thicknesses by bringing the parts corresponding to the upper faces into contact.
• the assembly can have two or more parts depending on the desired width. All combinations are obviously possible starting from elements coming from the same felt and therefore of the same thickness or from several felts of different thicknesses.
• FIG. 1 is a diagram showing the arrangement of the fibers in a traditional substrate
• FIG. 2 schematically shows the succession of steps leading to the formation of a cube for growing plants in which the fibers are arranged vertically
• FIG. 3 schematically shows the structure of a bread according to the invention
• FIG. 4 schematically shows the structure of a bread formed from several juxtaposed elements
• FIG. 5 shows the two stages leading to the assembla ⁇ ge of two elements by means of a sheath of a shrinkable material.
• FIG. 1 The mode of cultivation on traditional substrate is illustrated in FIG. 1.
• the substrate (1) rests flat on the ground or a support (not shown) which is substantially horizontal.
• the culture can be directly done on the substrate (1) but more usually we proceed in two stages.
• the plans are developed in a first step on cubes (2) and when their growth is sufficient and requires a volume of additional substrate, the cubes are placed on the substrate (1) in which the roots are propagated.
• This culture method often uses other elements, not shown, such as nutrient solution supply systems, tanks on which the substrates (1) are deposited to recover the excess drained liquids ...
• the unsheathed substrate (1) has been shown to show the arrangement of the fibers along traditionally substantially horizontal planes (3). It is common to coat the loaves of substrate with an envelope as indicated above.
• Figure 1 also shows the cubes (2) coated with a sheath.
• a protective film without being absolutely dispensable is very general and is due to the way in which they are usually produced, which is illustrated in FIG. 2.
• 2a the transverse cutting of a felt strip (4) from production. As previously in this strip of felt, the fibers are oriented in parallel planes, to the faces of this strip.
• the transverse cutting can be carried out for example using a circular saw (5) as shown diagrammatically or by any other equivalent traditional means for cutting the felts of mineral fibers.
• the first cutting of the strip results in the production of long parallé ⁇ lepipeds (6).
• These parallelepiped elements must then be cut into smaller elements. Due to their relative fragility, the cubes are, as indicated, coated with a plastic film.
• the sheathing operation for obvious reasons of convenience is advantageously carried out on the elements (6).
• the sheathing makes it possible to properly maintain the cubes (7) during their formation by cutting out the elements (6) as shown in 2a. As can be seen, this succession of operations results in the production of cubes (7) sheathed on four sides.
• the sheathed faces are shown hatched.
• the two free faces (8) are normally used to place the plants. Under these conditions it is understood that according to the most convenient technique abou ⁇ tit cubes in which the fibers are arranged in vertical planes, but this arrangement owes nothing to considerations concerning the culture itself.
• FIG. 3 shows the arrangement and the structure of a culture loaf (10) according to the invention.
• the use of this bread is analogous to that indicated in connection with FIG. 1.
• the fundamental difference the resides in the arrangement of the fibers. This has been shown diagrammatically so that the vertical planes appear, for example in (9).
• Figure 3 shows a monobloc bread obtained by cutting a felt thick enough to give a sufficient width to this bread, the thickness of the felt constituting the width of the bread.
• Figure 4 shows the two identical elements meeting, it is possible the same way to bring together elements of differentiated thicknesses thy or more than two elements to arrive at a full range of 'lar ⁇ geur breads.
• the faces of the felts (4) may have a surface layer which is denser in fibers and therefore less permeable to liquids or even to the roots. If this surface layer constitutes too great an obstacle, it is preferable to remove it in the assemblies such as that represented in FIG. 4 at least on the faces of the elements 11 and 12 brought into contact in (13). This removal is done by peeling equivalent to cutting the felt in its thickness and can be carried out for example by means of suitably arranged band saws.
• FIG. 5 A mode of assembly is shown in Figure 5. This involves joining the two elements (11, 12) by means of a sheath (14). To obtain a very stable assembly, it is proposed, for example, to form the sheath by means of a film of heat-shrinkable plastic material. In this case the two elements (11) and (12) are arranged in a sleeve (15) of the chosen film (FIG. 5a). This installation is very easy, the section of the sleeve being very large compared to that of the two elements. The assembly is spent a few moments in a heat treatment enclosure and the sheath retracts against the elements which it keeps tightly pressed against each other (FIG. 5b).
• the sheath used is usually black or white.
• the black color is preferably used when it is necessary to limit the heat losses at the level of the substrate. This is particularly the case for winter crops. When on the contrary it is necessary to preserve the substrate against an excessive temperature, white films are preferred.
• the density of the felt is approximately 40 kg / m 3 .
• the irrigation and temperature nutrition conditions “5 are those traditionally implemented by the station. Harvesting takes place between September 1 and September 30.
• the improvement observed in production can be explained by a better rooting of the plants itself resulting from a better environment, that is to say from a better adapted substrate.

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• Chemical & Material Sciences (AREA)
• Inorganic Chemistry (AREA)
• Life Sciences & Earth Sciences (AREA)
• Environmental Sciences (AREA)
• Cultivation Of Plants (AREA)
• Hydroponics (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=25672118

Family Applications (1)

Country Status (3)

Cited By (6)

Citations (4)

• 1988
  • 1988-08-12 EP EP19880907336 patent/EP0331692A1/de not_active Withdrawn
  • 1988-08-12 WO PCT/FR1988/000414 patent/WO1989001736A1/fr not_active Application Discontinuation
  • 1988-09-19 CA CA000577756A patent/CA1338795C/en not_active Expired - Fee Related

Patent Citations (4)

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