Raspberry sucker populations in non-cultivated alleys in a plantation of cv. Malling Jewel averaged 0, 0.5, 7.5 and 42/m2 in the first 4 years. The phasing of competition between alley suckers and the crop was examined by removing the first flush of suckers at different growth stages. No adverse effects were recorded over a 3-year period if suckers were left uncut until the tallest had reached a height of 75 cm (late June), in comparison with regular cutting. Delaying sucker removal until just before fruit harvest (mid-July) reduced yield, mainly as a result of reducing new cane numbers in the crop rows. The severity of yield loss on these plots increased, reaching 33% in the third cropping year. Sucker removal after fruit harvest (mid-August) or at the end of the growing season had no worse effect than removal in mid July. A second flush of suckers, produced following initial removal at heights of 25, 50 or 75 cm, had no effect on cane or fruit production. Counts in the final (sixth) year of the experiment (the fourth year of treatment) indicated that inter-row sucker populations were increasing on plots where first-flush suckers had been removed at or after the beginning of fruit harvest, relative to those on plots cut regularly in earlier years.