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Because the fibre hemp straw needs to be retted in the field for quite some time after harvest (§5§5.4) before it is stored dry for further processing, it is desirable that the hemp will not be harvested too late in the season. For this reason, varieties that flower early are most suitable;[1] in the Netherlands and Belgium, the risk of retting failure increases with later harvest time.
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Early flowering also means that the plants are slightly shorter than after late flowering, resulting in a lower yield in tonnes per hectare. Fibre hemp cultivation is a balance between fibre quality, yield, efficiency of harvesting and proper retting before dry storage to further processing.
TabelTable: Indicative characteristics of some fibre hemp varieties particularly suitable for textiles.[2]
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