The answer to 'why is my landscape lighting invasive plants' is that your landscape lighting may be attracting and encouraging the growth of invasive plant species. Landscape lighting can create warmer microclimate conditions that allow certain aggressive, non-native plants to thrive and spread more quickly than they would in the natural environment.
Some common signs that your landscape lighting is contributing to invasive plant growth include seeing more weeds, vines, or fast-growing plants around your lights, as well as noticing that some native plants are being outcompeted. To address this, you'll need to take steps to control the invasive species and modify your lighting setup to be less attractive to these unwanted plants.