A weed is a plant in the wrong place. Put a redwood in my garden and it would probably be the biggest weed in the world. Your question has no serious answer. Unless you mean smoking weed............
The Amazon is the worlds biggest rain forest
The Catholic Church is the biggest charity in the worlds.
the worlds biggest yoyo is about the size of a hobo
A plant becomes a weed when it's not wanted.
You don't plant weed, they just grow from gardens.
Sour Diesel
either a rose plant that eats flies or the worlds biggest pineapple.
A weed is an unwanted plant.
The worlds biggest island is clearly Green Land its PNG
The worlds biggest selling drink is both Milk and water.
The worlds biggest tin sheep here
Henna plant dye is prepared by making the paste of its leavesA weed and a plant really aren't two different things. A weed is a plant, it is just a plant you don't want