What is the most effective way to kill perennial weeds?

The most effective way to kill perennial weeds is by destroying underground vegetative structures. Perennial weeds often have extensive root systems or rhizomes that allow them to regrow year after year. By targeting these underground parts, you can effectively eliminate the plant's ability to regenerate. This method disrupts the plant's infrastructure, reducing its capacity to uptake nutrients and water, ultimately leading to its death.

Cutting them at the surface, applying water only, or using a low-nutrient fertilizer do not adequately address the problem. Simply cutting the weeds can encourage them to grow back even stronger, as many perennial weeds can resprout from what remains above ground. Watering does not eliminate the plants; rather, it can promote their growth. Fertilizers, particularly those low in nutrients, might inadvertently support the growth of the weeds instead of harming them. Therefore, targeting the underground structures is key to effective control of perennial weeds.