Preplant fertilization and fertigation in strawberry (Fragaria x ananassa Duch. cv. 'Korona') in an open field experiment

Effects of preplant fertilization and fertigation in strawberry were studied in a field experiment established August 2003 in South-Eastern Norway. Half the field was fertilized at planting and fertigated with a low nutrient rate from spring 2004 (T1), while the second half was unfertilized at planting and instead fertigated with excessive nutrient solution from spring 2004 (T1). In 2005, both treatments were fertigated with an equal fertilizer rate. None of the treatments caused any deficiency symptoms during the trial, but, of all parameters recorded, only the number of leaves and leaf area compensated for the early limitation in nutrients. Yield and berry size in T1 were significantly higher compared to T2 in the first harvest year, despite the low fertigation rate in T1. The following year, no significant effects of treatments were found. Leaves and petioles for chemical analyses were sampled several times during the trial for sap and dry matter analysis. Few significant differences between treatments were found, but it appeared that sap analysis provides most information on the present uptake in leaves. However, neither leaf dry mass analyses nor sap analyses reflect yield potential when conditions during plant establishment are suboptimal.