University of Illinois Extension

Fall Raspberry Patch Care

Taking good care of raspberries in the fall is important for future productivity of the patch, said a University of Illinois Extension local foods/small farms educator.

“Avoid over fertilizing and supplemental watering of summer-bearing red and black raspberries in the fall so that the canes can start hardening off,” said Maurice Ogutu. “Fall-bearing raspberries can benefit from supplemental water in dry weather in order to maintain quality and size of the fruit.

“Do not prune any raspberry cane at this time unless it is seriously damaged or diseased.”

You should only apply fertilizer and lime based on the soil test and plant tissue analysis. Some sulfur and magnesium containing fertilizers such as Sul-Po-Mag or Epsom salts can be applied at this time so that they can be leached to the root zones of the plants.

“Survey the patch to check what types of weeds are present, and decide on what type of herbicide to use,” Ogutu said. “If biennial weeds are present in the patch then you can control them with herbicides at this time.”

Control fruit rot in fall bearing raspberries by applying recommended fungicides, and harvesting frequently.

“Scout the patch for powdery mildew and apply recommended fungicides,” he said. “If phytophthora root rot is identified in the patch, treat the affected areas by drenching the roots with recommended rates of Ridomil Gold or Alliete in September or early October. You can also use other fungicides recommended in your state. “

He also recommended scouting the plants for crown borers. The borer adult is a moth that looks like a yellow jacket.

“Also check wilting canes to see if they are damaged by crown borer and determine if a crown borer larva is present in the crown. If so, remove the infected plants,” Ogutu said. “If the roots of the wilted canes are dark red in color then they have been attacked by phytophthora crown rot.

“Remove the infected canes and eliminate wild brambles growing near the patch.”