Nitrogen Rate, Irrigation Frequency and Volume Differentially Influence Growth, Flowering, and Nutrient Uptake of Container-Grown Rhododendron during the Following Growing Season

Sustainable nutrient and water management are critical for optimizing the quality subsequent landscape performance of nursery plants. In this 2-year study, we investigated influence different nitrogen (N) rates [N-free fertilizer (0 N) or N-free plus 7 (0.5 14 (1.0 mg N per day from NH4NO3] irrigation frequencies volumes [once daily to 50% 100% container capacity (CC) twice with same total amount as CC] on plant growth, flowering, uptake three rhododendron cultivars, including one deciduous cultivar, Rhododendron ‘Gibraltar’ two evergreen ‘P.J.M.’ ‘Catawbiense Album’. each case, plants were grown in soilless media year 1 transplanted soil 2. Increasing rate increased biomass content both years improved flowering following year. Furthermore, 1, once CC enhanced several nutrients cultivar growth cultivars. Plants that irrigated more frequently during performed better year, while those only cultivar. lower volume altered qualities, resulting a trade-off between flower production Our results indicate manipulating frequency can be used alter stock qualities improve landscape.