Dog is ripping plants out -_-

I have a 9 year old GSP x Kelpie x Lab; for some background; she grew up with another older dog who is now gone and she had training as a pup.

Recently, she has been pulling plants out of the garden, not really digging, more just ripping the plant clean out of the ground. I have never encountered this issue before and am so unsure how to correct this (she also does dig which is driving us mental but that's another, smaller issue).

We've tried spending more time with her inside and out, playing and getting more toys (she doesn't play with them unfortunately for us), she tends to do this behaviour when I am away from the home and when we return will hide from us as we have told her off for doing it.

Any ideas on what we can do to stop her from doing this? We've considered a small, decorative fence along the garden bed or sectioning off part of the yard so she can't access the spot (though we're worried this will encourage her to dig more into the grass).