From a gameplay mechanics perspective, sunflowers in 'Plants vs. Zombies' are purely support units—they don’t attack or block zombies. Their sole purpose is generating sunlight, the currency you use to plant defensive or offensive units like peashooters or wall-nuts. I learned this the hard way during my first playthrough when I tried lining the front row with sunflowers, thinking they’d at least slow zombies down. Nope! They got devoured instantly, and my strategy collapsed.
That said, creative mods or fan-made versions sometimes tweak sunflowers to have minor defensive traits, like a tiny health boost or a chance to 'dazzle' zombies with sunlight flashes. But in the vanilla game? They’re sitting ducks. It’s hilarious how they keep cheerfully bobbing their heads even as a zombie lumbers toward them—zero survival instincts.