PLUM HIGH DENSITY PLANTING – 10 YEAR TRIALS

Experimental plots of Japanese Plums Prunus salicina L. have been planted since 1979 on the coastal plain (Bet Dagan) and since 1980 on a lower-Galilee mountain (Giveat Hanania). Planting material was prepared mainly from hardwood cuttings of the cultivars: – Methley, Golden King, Santa Rosa, Cardinal and Songold; the more difficult to root, like Nubiana, Wickson, Laroda and Premier were pre-wounded at their bases, or mist propagated in comparison to grafted trees.

The maiden trees on their own roots developed slowly, but produced fruits earlier than on Mariana (2624) rootstock.
With a planting density of 4000–5000 trees/ha (2 m x 1.0– 1.25 m) moderately growing cultivars, like Wickson and Nubiana developed well and produced high yields from free spindle bush trees about 2 m high.

More vigorous cultivars like Methley, Golden King and Golden Japan required wider spacing of 2667–3333 trees/ha (2.5 x 1.5 m or 2 x 1.5 m), the last two grown as hedgerows, limited to 2.5 m in height.

By means of growth retardants, mostly Cultar (Paclobutrazol) soil treatment adjacent to drip irrigation, excessive vegetative growth was avoided.
Flower and fruit production have been promoted this way.

Fruit can be picked from the ground efficiently, but commercial expansion of the HDP system is still restricted by lack of suitable machinery for orchard management.

IV International Symposium on Research and Development on Orchard and Plantation Systems

D. Gaash, I. David, I. Ran

https://doi.org/10.17660/ActaHortic.1989.243.46