In view of the potential for kenaf as a viable paper-pulp crop for Italian areas, a field trial was conducted in 1992 in Cadriano (latitude 44°3 N, longitude 11°2 E) to estimate quantitative and qualitative crop performance as influenced by harvest date (114, 129 and 152 days after emergence, DAE) and irrigation. The productivity of two mid-late cultivars (BG 52-38-2 and Everglade 41) was positively affected by the length of the growing season and by the restoration of 100% of the crop evapotranspiration (ETc). Total dry yield of the rainfed crop was 10 t ha - 1 at early harvest (mid-September) and reached a 13 t ha - 1 plateau at late harvest (late October). Under well watered conditions crop biomass was 50% higher and it increased linearly with time, reaching a value of 20 t ha - 1 . The stem yield accounted for from 74 to 89% of the total biomass, and mean stem growth rates of 18 and 11 g m - 2 d - 1 were recorded for irrigated and non-irrigated crops, respectively. The bark content of the stem varied in relation to crop age and genotype and increased with time only in Everglade 41. Cellulose content in the bark was affected by harvest date, ranging from 54 to 56% at early and mid harvest to 61.6% at the latest harvest, and by irrigation, which favoured a similar increase. Positive relationships (r between 0.64 and 0.74) were found between growth traits (total and stem dry yield, stem height and basal stem diameter) and cellulose accumulated in the bark.