A Fleshy Bulb is an item dropped by Lureplants when killed. When planted by the player, it will spawn a new Lureplant. If the newly spawned Lureplant is killed, it will also drop a Fleshy Bulb. Despite being plant material, Fleshy Bulbs cannot be eaten and do not spoil.
It will take 2 days for a freshly planted bulb to turn into an active Lureplant, and taking its lure will reset the Lureplant to its "just planted" state. Bulbs planted too close to each other will block the movement of the player and Mobs.