A well-balanced nutrient solution for raspberries
A well-balanced nutrient solution for raspberry production on substrate is the key to healthy growth, reducing susceptibility to pest and disease and optimizing flower and fruit quality. Primocane raspberry cultivar 'Kwanza' is highly productive and lends itself to a single crop during one season. The production method shows a lot of similarities with a typical floricane culture however much greater yields can be realized. Despite these efficiencies fruit quality during autumn in the greenhouse is often critical. Reduced fruit firmness and a typical weakening of the skin are among the most important shortcomings of the cultivar. An optimal fertigation strategy for 'Kwanza' has been the subject of several years of research with particular attention to the effect of the level and ratios of various nutrients in the fertigation scheme on fruit quality while maintaining its productivity. It is generally recognized that from fruit set onwards the plant demand for potassium strongly increases. Old and senescing leaves show symptoms of potassium deficiency readily commencing then. Research over the past three years clearly indicates an important increase in the plant demand for potassium already prior to fruit set and more particularly from the commencement of flowering. This information is important to estimate when a grower must switch from a vegetative feed regime toward a more generative one (higher potassium concentrations). High potassium concentrations in the nutrient solution during fruiting (generative phase) in 'Kwanza' are used to overcome the earlier described shortcomings of the cultivar, however, a higher number of misshaped fruits and a greater incidence of dry sepals on fruit is often observed. A study on different mineral elements important for plant growth was performed to obtain a well-balanced nutrient solution for the cultivar 'Kwanza'.
Boonen, M., Putzeys, P. and Bylemans, D. (2020). A well-balanced nutrient solution for raspberries. Acta Hortic. 1277, 233-238
raspberry, fertigation, vegetative/generative, nutrient solution, substrate