How to Eradicate Mexican Petunias
- 1). Use your spade to dig up the entire Mexican petunia plant, along with as much of the root system as you can manage.
- 2). Clip new sprouts with your garden shears. Make a clean cut at the base of the sprout.
- 3). Pour liquid glyphosate, an herbicide that kills both weeds and perennials, over the sprouts that you have just clipped. You can also use an eyedropper for better control.
- 4). Repeat steps 2 and 3 until the plant is completely removed from your garden.
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