Every year I grow F1 hybrid cucumbers in my greenhouses (not in the same place), and every year as they get to full size they are covered with silver grey streaks, which although don't spoil the cucumber, they don't look very nice. Can you tell me what these marks are and how to prevent them? I grow organically so don't want to use chemicals for control. Thank you.
Certified GKH Gardening Expert
It sounds like they are experiencing cracking, which is uncommon with cucumbers but possible. Cracking is normally caused by irregular watering- going through dry period and then a heavy watering. The plant, being water starved, sucks up the water rapidly and over fills its fruit with water. Small cracks form (you can kind of think of them as stretch marks on fruit) and they heal quickly, but leave scars that get bigger as the fruit grows. The fruit tastes fine and is fine, but looks a little marred. Making sure they are evenly watered will correct the problem on future cucumber fruit.