AN ORGANIC VERSUS A CONVENTIONAL FARMING SYSTEM IN KIWIFRUIT

To determine the feasibility of growing kiwifruit organically, a kiwifruit vineyard converted to an organic farm was compared to a conventionally farmed vineyard from 1990 through 1992. January or March applications of composted chicken manure (organic system) or NH₄NO₃ plus CaNH ₄(NO₃)₃ through micro sprinklers during the growing season (conventional system) were applied to give nearly equal rates of 168 kg N ha^-1. Soil analysis showed a trend toward a higher pH and organic matter over time for the organic system.
In 1992, there was a trend for the organic system to have higher NH₄-N and lower NO₃-N concentration in the soil.
Leaf nitrogen levels from the organic system were consistently lower than those from the conventional system but were not deficient.
Leaf concentrations of sodium and chloride increased over the three-year period in the organic system but not to phytotoxic levels.
Leaf zinc levels were adequate and increased over time in both systems.
Organically grown fruit was as firm as or firmer than conventionally grown fruit at harvest and four months after harvest.
No differences were seen in percent soluble solids content.
Damage from latania scale and omnivorous leaf roller was small in both systems except scale damage in the organic system in 1992. An economic analysis of the cultural practices showed that the organic system cost almost $720 per ha more then the conventional system.
The grower reported fewer repack losses for organically grown fruit in 1992. We conclude that growing kiwifruit organically is feasible if an economic premium is received.

III International Symposium on Kiwifruit

J.K. Hasey, R.S. Johnson, R.D. Meyer, K. Klonsky

https://doi.org/10.17660/ActaHortic.1997.444.33