Problem: Invasive plants
If you love lilies and black-eyed Susans, but
hate the way they're taking over your garden and choking
out other plants, here's what you can do:
Many plants multiply by dropping seeds and by sending out roots that establish new plants. A layer of mulch will prevent the seeds from taking root. But to stop those aggressive roots, you need a solid barrier. Replant the spreading plants inside underground “corrals.” The plastic corrals should extend at least 10 in. below ground to prevent the roots from sneaking under them. This trick won't work with plants such as strawberries or mint that spread above ground.