Readers' Top 10 Gardening Mistakes

Mistake 5: Planting an Invasive Variety

"We planted a horseradish plant in a corner of our garden and were pleased with the crop we harvested the following season. We pulled it all up, tilled the garden in spring, planted for the season, and there it was—popping up all over the place! I never knew how invasive a plant could be."
Cynthia Sadowski Lawless
Southington, Connecticut

Garden Fix

Plants like horseradish, English ivy, Mexican feathergrass, and spiderwort are notoriously invasive in gardens and are best grown in containers, says Pam Penick, an Austin, Texas-based garden designer and writer of the blog Digging. If you order seeds from a catalog, look for words like prolific reseeder and vigorous growth, which often indicate invasive tendencies. If you do choose to plant an invasive variety, weed diligently. And consider solarizing: Dampen the soil, spread a black plastic tarp over the weeds you want to kill, and secure the tarp’s edges with rocks. Leave the plastic in place for a few months while the weather is hot. The plastic will heat up the soil and kill off the weeds.