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Tiny black worm type grub

Hi I have been growing tomatoes in the greenhouse in grow bags for years and never come across this problem. Tiny black grubs/worms eating leaves and tomatoes; appear to be in the soil also. 
Help/advice appreciated. Many thanks


  • LynLyn Posts: 23,064
    Are you sure those black things have legs and are actually moving about.  It’s sounds like caterpillars are eating the leaves and those are droppings. 
    Gardening on the wild, windy west side of Dartmoor. 

  • I feel a bit silly now😂. They're not moving but I can't see any caterpillars?  I've taken all the leaves off and any damaged tomatoes. I suppose the caterpillars could be inside the tomatoes? 
  • LynLyn Posts: 23,064
    Can you see holes in the tomatoes?  I doubt whether that would happen, they usually just eat green stuff.  Don’t take too many leaves off, the plant needs them for a while yet. 
    Dont feel silly, there are grubs that live on lilies that look exactly the same,  they cover themselves in their own excrement for safety.  
    Gardening on the wild, windy west side of Dartmoor. 

  • FireFire Posts: 18,068
    Someone else ask the same question here a few days ago, so please don't feel daft.
  • I've only taken damaged leaves off. Yes there are holes in some tomatoes but can't see anything inside, just the black ? droppings around the edge of the damage.
  • LynLyn Posts: 23,064
    I would take those red ones off they’re ripe and ready, cut one in half and see what’s inside. 
    Gardening on the wild, windy west side of Dartmoor. 

  • They can also be snail droppings.
    In our polytunnel every day I come across snails "hiding" underneath the battens and you can see their droppings on the covering.
    The snails are removed fairly quickly.
  • LynLyn Posts: 23,064
    Slug and snail droppings are like a thinish black line that curls up in a wiggly thing.
    Heres a fresh snail dropping, just freshly taken

    Gardening on the wild, windy west side of Dartmoor. 

  • They look very similar and I've just come across a couple of slime trails. I will go on a snail/slug hunt. Many thanks 
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