DETERMINATION OF THE OPTIMAL SHOOT LENGTH AND PRUNING STRATEGIES IN 'BOURJASOTTE NOIRE' FIG

The European fig cultivar ‘Bourjasotte Noire’ was recently introduced to the Western Cape Province of South Africa. Producers struggle to implement effective commercial practices that will optimise yield of quality fruit. A phenological study was conducted to establish the optimum one-year-old shoot length to maximise yield and optimise fruit size. Yield, fruit size, bud break and shoot growth on one-year-old shoots (N shoots) comprising four different length categories were evaluated. All four categories seem to be suited for reproduction and should also produce a fair yield the following season. Various pruning methods are described in fig production literature, depending on cultivar, crop of interest and climate. Two experiments to establish pruning methods that will optimise yield were conducted. Experiment 1 comprised four treatments consisting of an unpruned control (T1), removal through heading of either one-third (T2) or one half (T3) of N shoots, or cutting N shoots back to three nodes (T4). Treatments were applied to the whole tree on 9 August 2008. Experiment 2 comprised six treatments: an unpruned control and five pruning dates ((30 June 2008 (Date 1), 21 July 2008 (Date 2), 11 August 2008 (Date 3), 1 September 2008 (Date 4) or 22 September 2008 (Date 5)) where one third of the N shoot was removed by heading. One treatment was applied per tree, to three selected shoots. In experiment 1 it was established that removal of one third of N shoots by heading should ensure the development of shoots that can sustain production, without a negative effect on yield. Data from experiment 2 suggests that N shoots of ‘Bourjasotte Noire’ should be pruned on 21 July (mid-winter) (southern hemisphere) to produce long N+1 shoots for sustainable production, without having a negative effect on yield in the current season.