Application of nitrogenous fertilizer or premature autumn defoliation prevented the water content of raspberry canes from dropping in midwinter to the low levels of untreated plants, apparently because the canes did not become fully dormant. This effect was correlated with a delay in response to spring conditions, possibly because the delay in becoming dormant caused the canes to remain dormant for longer. Potassium had the opposite effect to nitrogen.
In canes of the cultivar ‘Malling Promise’ the water content remained high and fluctuated even in early winter, apparently in response to temperature variations. In ‘Lloyd George’ the water content decreased in midwinter and did not respond to spring conditions until a later date than in Malling Promise, whilst in ‘Norfolk Giant’ it did not increase until a very late date.