Sometimes when I slice cukes from my garden, there are holes that seem to run the length of the cucumber. I've never found a worm. What could be causing this?
Why Do I Get Tunnels or Fissures Inside My Cukes?
What your describing suggest your cukes are reacting to uneven watering. If the middle has not filled out the fruit is not fully matured as well. Normally insect damage of cucumbers don't appear as you described.
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