Perennial weeds are tricky garden invaders because they can sprout from seeds, root pieces and stems. Common perennial weeds include tree of heaven, Canada thistle, dock and dandelion.
Easy Solution: Learn to identify weed seedlings. As soon as you spot a perennial weed, get on your hands and knees and dig it out. This broadleaf dock sinks a deep taproot quickly. Getting all of it out of soil is the key to keeping this perennial weed from coming back.