Effect of Nutrient and Water Management on Nutrition and Growth of Young 'Cristalina' and 'Skeena' Sweet Cherry on Gisela 6 Rootstock

Growth and nutrition of 'Cristalina' and 'Skeena' sweet cherry on the dwarfing rootstock Gisela 6 were monitored for the first three growing seasons in a split-split plot, randomized, replicated experiment testing the effects of irrigation frequency (started year 2) and different soil management strategies. Main plot units compared high frequency (I1) irrigation to low frequency (I2) irrigation by applying the same quantities of water as determined by atmometer measurements of evapotranspiration either 4 times daily for I1 or every second day for I2. Soil management subplots compared a wood waste mulch or annual fertigation of P at bloom to control treatments all receiving annual fertigation of N and commencing in year 3 fertigated K. Each subplot contained both 'Cristalina' and 'Skeena' cultivars. Trunk cross-sectional area (TCSA) was increased by I1 relative to I2 irrigation regime, was greater for 'Skeena' relative to 'Cristalina' and was increased for the mulch treatment but only at I1. Volumetric soil moisture content at 0.20 cm depth was significantly lower under I2 relative to I1 when measured immediately prior to I2-irrigation. Reduced TCSA was directly associated with reduced soil moisture contents for 'Cristalina'. Annual P applications at bloom and I2-irrigation increased fruit numbers but these effects need assessment as crop load increases from current minimal levels.