Q • Can you tell me what should be done with the long straight canes that are growing on my raspberry bushes now? We enjoyed a fine harvest this year, but those straight shoots don’t have any fruit on them.
A • Their roots are perennial, but individual stems (canes) of bramble crops only live for two years, then die.
As soon as your harvest of summer-bearing raspberries is over, remove all the stems that bore fruit, cutting them off at ground level. Those long, new shoots will produce next year's crop. They can be thinned out now to establish a spacing of about three to four healthy canes per square foot. If you prefer, these tasks can be put off until winter, when plants are dormant.
Remove any canes that are broken or spindly, but leave the others to grow untrimmed for the remainder of the season. In late winter these canes can be “tipped” back by about one-fourth their overall length, but no shorter than 5 feet in height.