Completely understandable to want to bring one's hard work with them upon moving. It sounds like the landlords just wanted to benefit off the hard earned improvements that she made.
What kind of lowlife threatens someone's dog? Someone who is in dire need of a wakeup call. And oh boy, did these neighbors receive that wakeup call. It came in the form of a cool and calculated pro revenge that employed an army of dandelions to get the job done. Just picturing the look on those neighbors' faces when they saw all those weeds surfacing. They must've been beside themselves.
Check out another neighbor pro revenge story with these neighbors that went full petty, so the guy towed in a pro revenge.
We've got a good old-fashioned tale of revenge meets neighbor wars here, folks. It sounds like the savagely named, "Megab*tch" neighbor was crossing all kinds of literal lines, when she went ahead and hammered long and dangerous nails into the family's fence. Apparently the motivation behind this was so that she could hang some potted plants. Her mean and blindly selfish attitude certainly didn't help things.
Good luck trying to cut it down without making a scene that all your male neighbors will cringe just thinking about. ouch