Flower Bud Differentiation and Flowering of Tray Grown Strawberry 'Nyoho' as Affected by Plant age and the Duration of Nutrient Starvation

In the forcing production of strawberry Fragaria × ananassa Duch., the use of tray plants grown from cuttings of runner tips is becoming popular with the increase in strawberry production with substrate culture systems, due to their lower cost and ease of plant management compared to conventional pot-grown plants. Effects of the date of runner cutting and the duration of nutrient starvation on flower bud differentiation and flowering of tray grown plants of strawberry 'Nyoho' were investigated. Plants cut on mid or late July and rooted on cell trays performed early and uniform flower bud differentiation and flowering compared to June or August cut plants. When the plants were supplied nutrient solution containing ca. 6 mg-N/plant/week, nutrient starvation from the end of August led to the early and uniform flowering of tray plants, outperforming the earlier or later starvation.