Thorny flower

Spiky Plants are strange, round plants with red spikes seen in Super Mario Galaxy and Super Mario Galaxy 2. They come in a normal size and a huge size. They hurt Mario/Luigi when touched, so the only way to destroy them is by attacking them with something else, like a Stretch Plant or a coconut, or by being pulled and eaten by a Yoshi. Some Spiky Plants, after being destroyed by a coconut, will reveal a Sling Star or Launch Star leading to the next planet.

There are three kinds of variants, the standard variant, the bigger variant and the floating variant. The floating variant is more common in certain galaxies, including the Gusty Garden Galaxy, the Yoshi Star Galaxy, and the Tall Trunk Galaxy.

When touched by the Co-Star Luma, Spiky Plants will retract their spikes, allowing Mario to pass over them safely without needing to destroy it.