The effect of poor drainage on the root distribution of kiwifruit vines

Kiwifruit vines growing in poorly‐draining soil on recontoured land had smaller root‐systems and markedly fewer structural roots than nearby vines on undisturbed well‐draining soil. The vines had been growing for 3 years before it was realised that there was a problem. Occupied rooting volumes, mean root‐length densities (cm root/cm 3 soil), and root weights (kg/plant) were lower under the kiwifruit vines on the poorly‐draining soil. Rainfall data for the region demonstrate how growers could become over‐confident about the health of their vines during several years of low or average rainfall. Waterlogging symptoms may only became obvious on a poorly‐draining soil after a higher than usual rainfall.