Farm Diversification

Flax is traditionally used for high quality linen production requiring exacting production conditions.  Prior to harvest, the crop is cut and left in rows in the field before being turned.  The stems are therefore evenly exposed to sunlight and precipitation to facilitate a process of retting, which breaks the pectin bonds between the long fibres and the central core of the plants. 

Linen production is now largely restricted to flax cultivated in France and Belgium and processed using traditional methods.  Existing markets for fibres include the paper industry (for speciality papers) and non-wovens (for biocomposites).  The core of hemp stems, the hurd, is used for animal bedding.

The expansion in markets for natural fibre products is creating considerable new interest in these crops, including as biocomposites for car components and in the construction industry where they can be used as insulation materials.  Techniques have also been developed to combine the hemp core with lime to produce a robust building material for construction where its qualities of high levels of thermal insulation and excellent strength characters are of note.

Flax and hemp are both spring- sown. 

For hemp, sowing should occur once soil temperatures have raised to ensure rapid establishment and competitiveness against weeds.  Sowing rates for hemp are in the order of 180 seeds/m2.  A stale seed bed technique is useful combined with the application of a pre-emergence broad spectrum herbicide.  Fertiliser should be applied at rates of 80 – 120 kg N/ha, 60 kg P/ha and 120 – 150 kg K/ha.  Hemp flea beetle may be seen but seldom justifies treatment.  The diseases Botrytis and Sclerotinia may also occur. 

In order to achieve separation of the fibre from the woody core, the hemp crop should be mown and than left in the field to achieve some retting.  The crop is then baled and stored under cover to maintain fibre quality.  Average yields of fibre from hemp are 7.5 t/ha.  Dual hemp gives yields of approximately 1.25 t seed/ha with a sraw yield of 5 t/ha. 

Some development of the use of glyphosate to ret flax have taken place.  The application of glyphosate allows the crop to partially ret whilst still standing. Allowing easier combining. 

Recent contract prices for hemp have been around £450/tonne for seed and £120/tonne for straw.

Hemcore is currently the only company in the UK operating a commercial decorticator.  The processing facilities are based in Essex and as straw is a bulky product and therefore expensive to transport, geographic range of the crop is limited with most crops being grown in the Eastern counties. 

With the anticipated development in the construction market for renewable products, expanstion of processing capacity is planned and Hemcore pla to construct 3 – 4 regional processing facilities located in proximity to main growing areas.

The development of regional or mobile processing equipment is particularly important in order to allow northern growers to capitalise on fibre crop opportunities.

Processing of fibre crops involves 2 stages.  The first stage is to separate the fibres from the woody core stem in a process called decortication.  The fibres will then undergo further processing for the end market. 
Economic potential