I have few gardening regrets, but those I do have largely involve unwanted groundcover plants. Groundcover can be incredibly valuable, but invasive ground cover plants are thugs, and what might start out as one small, innocent-looking addition can quickly turn into a rampaging monster.
I learned this first-hand after planting a single sweet woodruff in a corner of my own backyard. Oh boy did it spread, and when I tried to remove the thick dense mat it created, bits of rhizome (root) broke off and were accidentally transferred around the garden, spreading the problem.
