I have a plant eating bugs would normally be taken to imply that the plant is actually eating bugs at the moment, rather than that it was a plant which does eats bugs.
I think this is because if you undo the Whiz deletion,
I have a plant eating bugs.
I have a plant which is eating bugs.
This is a different claim from
I have a plant which eats bugs.
There is no way to perform Whiz deletion on that, because there is no "is".
On the other hand,
I have a bug-eating plant.
does not usually imply that the eating is going on at present, because "bug-eating" is normally interpreted as a specifying the kind of plant rather than an ephemeral property.