Terraria - How To Find Plantera Bulb Easiest Way [duplicate]

From the wiki:

Plantera's Bulbs emit moderate light and appear in the minimap in areas the player has already explored. They spawn one at a time after a delay of about half a day between them, and unless destroyed, several will eventually be present (10-15 in a small world's naturally-generated Underground Jungle). If destroyed, they respawn after the same delay (though not necessarily in the same spot), allowing the player to summon Plantera an infinite number of times.

While I cannot find the link now, there used to be a guide on the wiki for farming Plantera's Bulb, and following it helped me on later runs. The idea is basically to make a second area of underground jungle somewhere well away from the normal jungle, and give it large areas of flat jungle grass. The design that I saw was a large room with a stack of one tile thick mud and jungle grass platforms. The platforms also had actuators behind them so that you could quickly turn the room into an open area for actually fighting Plantera.

The explanation in the article, although I cannot vouch for its veracity, was that one bulb spawns per time period, per isolated jungle region. So if you made a reasonably sized jungle region then you could find it more easily.

You should also note that the bulb requires a flat patch of jungle grass at least two tiles wide.

In my experience this patch must also be empty, but I have no other sources to back up that assertion. So you may need to periodically remove bushes and tall grass. This can also help with getting it to spawn in regular jungle areas. They tend to get overgrown and need to be

You should also note that Plantera's bulb does not spawn until after you have defeated all three mechanical bosses. Your question does not indicate that you have done so.