SEASONAL PATTERNS OF GROWTH AND TISSUE NUTRIENT CONTENT IN STRAWBERRIES

At monthly intervals during the establishment year, 90 strawberry plants were excavated and separated into component parts, dried, weighed, and nutrient analyses were performed on the tissues. When growth resumed in spring, biomass and foliar nutrient levels were again measured until fruiting. Individual plant growth was linear during the establishment year, with leaves accounting for the highest percentage of accumulated biomass. In general, nutrient concentrations during the establishment year either remained relatively constant, or declined. The percent increase in biomass accumulation was always greater than the percent decline in nutrient concentration, indicating that strawberry plants have a continuing demand for nutrients during the establishment year. About 50% of the biomass was lost during the winter, mainly in foliage. However, within six weeks of resuming growth in spring, plant size was equivalent to that of the previous autumn. The root system was the only tissue to exhibit a reduction in biomass during fruiting. During this time, foliar nutrients displayed very different concentration patterns. Although this period of fluctuating nutrient levels is generally avoided for leaf sampling and analysis, it is likely that this is when nutrient limitations will have their most pronounced effects.