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Micro-irrigation, fertigation, and mulching have been proposed to improve the nutrient and water-use efficiency of crop production. The effect of these management practices on the emission of nitrous oxide (N2O) from vineyards is not well understood and most prior studies were short-term (<1 year). To investigate longer-term effects, a study was conducted in grape (Vitus vinifera L. cv. Merlot planted in a sandy loam soil in British Columbia, Canada. The experiment was a factorial treatment design consisting of two micro-irrigation types (Drip or Micro-sprinkler), two nitrogen sources (surface applied Compost or fertigated Urea at a rate of 40 kg N ha(-1)), and two vineyard floor managements (bark Mulch or "Clean"-meaning bare soil). Frequent measurements of N2O flux and soil and environmental variables were made over two complete years (2013 and 2014). A considerable portion (37% in 2013 and 61% in 2014) of the annual cumulative N2O emission (Sigma N2O) occurred during the pre-growing season particularly within the thaw period. In 2013, the annual area-scaled Sigma N2O emissions for Drip was x Micro-sprinkler, Urea was approximate to 1.5 x Compost and Clean was approximate to 1.7 x Mulch. In 2014, Sigma N2O emissions were over 14% higher, likely due to more freeze-thaw events, higher soil mineral N availability (47% higher), but treatments differences were not significantly different. Analysed over two years, micro sprinkler reduced growing season emissions by 29% and surface application of bark mulch decreased annual area-scaled and yield-scaled Sigma N2O emissions by 28% and 23%, respectively, suggesting bark mulch as a strategy for mitigating N2O emission. The observed interannual variability in the total N2O emissions suggests that at least a minimum of 2 years of continuous study may be required to estimate representative annual N2O emission budgets and to recommend N2O mitigation strategies in vineyard systems. (C) 2016 The Authors. Published by Elsevier B.V.