YIELD AND FRUIT SIZE OF BLUECROP AND BLUERAY HIGHBUSH BLUEBERRIES AT 3 PLANT SPACINGS

The influence of in-row plant spacing on the yield and fruit size of ' Blueray' (erect growing) and 'Bluecrop' (spreading) highbush blueberry (Vaccinium corymbosum L.) was studied. Plants of both cultivars, spac ed at 0.61 m within the row, had significantly higher yields per hecta re than plants grown at wider spacings (0.92 and 1.22 m) in each of fi ve harvest years. On a per-plant basis, however, plants spaced at 1.22 m had higher yields in the last two harvest years of the experiment t han plants spaced more closely, which indicated that interplant compet ition reduced per-plant yields of closely spaced plants as plants grew larger. Over the 5-year harvest period, plots with 0.61-m plant spaci ng produced a cumulative total yield of 17.24 t.ha-1 more than plots w ith the conventional 1.22-m spacing. Plant spacing did not affect frui t size in this experiment.