What do you call any plant that is growing where it is not wanted?

A plant that is growing in an area where it is not desired is referred to as a weed. Weeds can be any type of unwanted plant, typically characterized by their rapid growth and ability to thrive in a variety of environments, often competing with cultivated plants for nutrients, light, and space. They can hinder the growth of desired crops, landscape plants, or any other species that are being tended to.

In contrast, invasive species typically refer to species that are not only growing in unwanted areas but also cause significant ecological damage due to their ability to outcompete native species and disrupt local ecosystems. Native plants are those that naturally occur in a specific region without human introduction, while flowering plants are a broad category that includes any plants that produce flowers, whether they are weeds, cultivated, or native. Thus, the term "weed" specifically captures the essence of unwanted plants in a given context, making it the most accurate term for this scenario.