Is it necessary to order five big buttons?

In the game Plants vs Zombies, it is very necessary to upgrade Dakouhua to the fifth level. The main function of the fifth-order big mouth flower is to devour and destroy zombies. When it is wide enough, it can kill all the zombies in the first three squares, no matter whether these zombies are high-order or non-giant, they can achieve the effect of killing. Therefore, it is suggested to upgrade the big mouth flower to the fifth order.