If it does, just observe what attack it is. If a tentacle is swinging hostilely, move to another area of the room. If the tentacles dig into the ground, watch for a cloud of dust (?) and avoid it - the tentacles will sprout from the ground and damage you. When have cut all of the 20-ish vines, the bulb falls to the ground, beginning the second phase of the battle.
Inside the flower, you’ll find the Boko Baba-thing. MAKE SURE TO L-TARGET IT! This bulb will remain open for only a short time - you need to make every attack count
I highly recommend staying in the flower the whole time, despite the fact that you will indeed take 1/4 heart damage as the bulb, when it closes and reattaches to the ceiling, will spit out Link. However, it means a few more hits, and you can restore health by the rocks and skulls in the room. Repeat this process until the battle is over.
At the end of the battle, the Boko Baba thing becomes severed. It thrashes through the air and on the ground until it blows up, leaving Makar and a complete Heart Container behind.
As for the flower, it turns a grey color as a whirlwind appears in the center of it. Makar thanks you for rescuing him, then remembers that the annual Korok ceremony is today and that he must leave at once. Grab the Heart Container and enter the whirlwind.