The effects of summer shoot tipping and rootstock on the growth, floral bud production, yield and fruit quality of young sweet cherries

SummarySummer tipping of the extension shoots of cvs Van and Merton Glory sweet cherries consistently reduced mean shoot length and tree size. The effects on total growth and shoot number were variable. Total floral-bud numbers per tree or per metre shoot length were occasionally reduced but more often unaffected by the treatments. The numbers of floral buds on 1-year-old shoots were doubled following tipping treatments. The timing of tipping had no effect on mean shoot length reduction; however, later timings induced the growth of more shoots than early tipping. Fruit set on spurs was reduced by tipping in one year but unaffected in two others. Set of floral buds on 1-year-old wood was increased by tipping at all timings tested. Later tipping treatments increased fruit soluble solids and, occasionally, fruit size, and reduced the numbers of fruits with aborted seeds. Mean shoot growth and, occasionally, total shoot growth of both scions were much reduced on the rootstock Colt. The two cultivars differed in their response to the rootstocks and/or the tipping treatments in some years.