I bought a home with planters filled with ribbon grass. They are almost wild and I want to stop it from even getting crazier. I attached a photo so you can see.

I would love to put some flower in this planter. Flowers are both from indoor germination and from pots. So I plan to remove these ribbon grasses. How does one remove the grasses and ensuring that they won't interfere with the new flowers I will be planting? I read somewhere that the ribbon grasses may come back, but I want to know if they will even hinder the growth of my flowers? I do not mind if they come back but not stop the growth or even kill my flowers.

To make it simple: what is the best way to remove these ribbon grasses so I can start planting my flowers. I also read that digging up and then pouring boiling water is a way, but I am scared that the jasmines (they are the ones on the wall in the photo) might get affected if I do the boiling water method.

I appreciate any advice out there. I am just eager to personalize our new home.