Hello, and welcome back to another week of plant advice with the Aspiring Gardener! This week, we’re talking about aggressive plants. By definition, an aggressive plant is one that spreads faster than preferred and/or grows into unwanted places, like the ivy crawling into my basement. Many aggressive plants also happen to be invasive ones. When they’re brought over, whether accidentally or on purpose, they outcompete native species and spread rapidly through the region. In California and Butte County specifically, some of the worst offenders are Yellow Star Thistle, European Beachgrass, South American Spongeplant, Alligator Weed, and Cheatgrass. Cheatgrass and several other grasses like it are problems in particular due to their high flammability. They make it all too easy for wildfires to spread. That being said, aggressive plants aren’t inherently bad.
Some aggressive plants, like Coyote-brush, make excellent groundcovers and also happen to be native. Others, like field mint, might not be good ground covers, but they certainly provide a lovely scent and a tasty addition to the kitchen! If you want to garden with an aggressive plant, be sure to take steps to ensure they don’t envelop your yard. Those that spread through rhizomes (underground and horizontal growing stems) should be planted in secure containers, and those that spread overland should be continually pruned to prevent further spread. Unfortunately, there’s little to be done about the spread of seeds through wind or various wildlife outside of normal precautions, but that’s what weeding is for. Stay safe, be vigilant, and happy planting!