BUD BREAK: SAFE AND EFFICIENT METHOD OF OVERCOMING WINTER DORMANCY - NEW ZEALAND EXPERIENCES WITH 'HORT16A' AND 'HAYWARD' KIWIFRUIT

Different strategies and chemical compounds have been tested to overcome poor bud break when winter chilling requirements are not satisfied in subtropical conditions. Only some solutions are successfully applied in the field. In the warm temperate NZ climate three years of trials with an E.C. fertilizer, nitrogen solution with calcium , testing different rates on ‘Hayward’ (only one rate has been tested on ’Hort16A’) and timing of application, starting from 50 days before natural bud break, the most important variable, gave good result on ‘Hort16A’ and ‘Hayward’ bud break. Bud break was generally a week earlier than in the untreated controls and was uniform along the canes. Generally percentage bud break was increased, +15% above controls ‘Hort16A’ and more flowers per winter bud (+58%). More fruit per unit area is expected compared to the controls (+19%.) Despite the higher number of fruit per hectare, the fruit size of untreated vines (115 g) was not significantly different from the treated fruit (112 g).