Grape Yield and Quality Response to Cover Crops and Amendments in a Vineyard in Nova Scotia, Canada

Abstract

The increasing cost of synthetic fertilizers, combined with their associated environmental impacts and yield instability, has promoted the use of local waste products and cover crops in vineyards. We assessed the effects of cover crop mixtures combined with organic and industrial wastes on grape yield and quality over two full growing seasons in a vineyard (Vitis vinifera) in Eastern Canada. The experimental treatments were arranged in a nested design with three replicates. Four cover crop mixtures: (i) oats + pea + hairy vetch (OPV), (ii) oats mixed with red clover (ORCl), (iii) timothy + alsike + red clover (TM), and (iv) control with no cover crop (CONT) were applied to main plots and five fertility treatments (fertilizer without N [NDEF], full synthetic fertilizer [FERT], wood ash [WA], municipal solid food waste [MSFW], and mussel sediment [MS]) were applied to subplots. During the second growing season, only half of the subplots received fertility treatments. Grape yield for the most productive cover crop and amendment combinations were ORCl × MS (9.52 mg/ha) > OPV × MSFW (9.49 mg/ha) > TM × WA (8.81 mg/ha) > ORCl × MSFW (8.28 mg/ha). The lowest grape yields were obtained with combinations of CONT with either NDEF (3.86 mg/ha) or WA (3.61 mg/ha). The highest berry sugar concentrations among the cover crops were obtained under TM floor management combined with NDEF (16.43 Brix), MS (16.03 Brix), and MSFW (15.98 Brix). Grape yield was affected by cover crop only during the second growing season, but berry sugar was not. Cover crop floor management strategies and organic or industrial wastes can be used as sources of nutrients or soil conditioners for vineyards in the cool humid climate of Eastern Canada.