Reduced Nitrogen Fertilizer Rates Maintained Raspberry Growth in an Established Field

Optimizing nitrogen (N) fertilizer rates maintains good red raspberry (Rubus idaeus L.) production while alleviating environmental risks. Although growers in Washington are using the caneberry nutrient management guides derived from western Oregon, these may not be appropriate for other regions given differences climate, soil type, and crop productivity. However, limited research has been conducted to observe impact of N rate on floricane growth, yield, fruit quality Washington. The aim this study is evaluate response “Meeker” raspberries grown northwest Washington, USA, different order provide information future local guides. Treatments urea (46% (N)) were surface-applied raised beds established ‘Meeker’ plots at controls, low, medium, high (0, 34, 67, 101 kg ha?1, respectively) 2019 2020. experiment was arranged a randomized complete block with three replications. Fruit yield quality, plant growth leaf tissue concentrations, characteristics evaluated. There no treatment effects characteristics, except titratable acidity ammonium (NH4-N) concentrations. lack due nutrients mineralized organic matter (3.81–4.0%) utilization reserves. Based results, level reserves should considered when making suggestions. Fertilizer costs as well potential pollution excess fertilizers could reduced through utilizing two sources nutrients. Furthermore, longer periods warranted understand how adjust based sustaining yields.