Sunflowers are undoubtedly the most powerful.

Sunflowers can emit sunlight, which is the foundation of all plants (except small mushrooms and sailor mushrooms). No matter what plant, it depends on the sunshine of sunflower. The sunshine of some sunflowers can be exerted by all kinds of plants.

From the overall strategy, we will find that sunflower is the most powerful. Sunflowers and zombies are eager to provide sunlight for other plants to kill zombies.