Bast fibre plants are attracting increasing attention in Europe, and the plant straw fractions have already been used as a raw material in many new applications. This study focuses on characterising the liquid–fibre interactions of frost-retted and unretted bast fibre plant ( Linum usitatissimum L. and Cannabis sativa L.) straw fractions. A novel approach was used in order to overcome the problems introduced by the surface heterogeneity in contact angle measurements. First, the wicking rates of water, oil and ethanol in plant straw fractions were measured with a capillary rise method. The results were compared with the results calculated from the Lucas–Washburn equation. Second, the wetting properties of a compressed sample were studied by measuring the contact angle of a liquid. Third, the absorption time of a liquid droplet on a compressed sample was measured. Fibre hemp absorbed water better than flax/linseed. After 100 s the difference was about one order of magnitude. For oil the differences were marginal. Wicking and wetting turned out to be very rapid even when the measured (static) contact angle was almost 90°. Big variations in dynamic contact angle calculated from wicking measurements were observed. The wicking rates and droplet absorption times give suitable information when selecting fibre plant straw fractions as raw materials for new industrial products. On the contrary, a droplet based contact angle measurement does not give useful information of dynamic wetting behaviour.