Flower Pot Drop

A character is taking a nice stroll, when suddenly a flowerpot falls out of Hammerspace and crashes onto their head. This is a Zany Cartoon trope used as a less extreme version of Anvil on Head.

Compare Anvil on Head and Piano Drop.

Examples of Flower Pot Drop include:

Anime

A couple bullies at Ouran Acadamy try to drop two flower pots on Kasanoda, but Mori knocks Kasanoda out of the way and hits the second pot to the side in mid-air.

Film

Parodied in Kung Fu Hustle, where the character doesn't get up after a pot is dropped on him from a top level apartment, and still played for laughs. When bad stuff starts happening, the recipient gathers the scattered dust around his head to hide.
In Homeward Bound II: Lost In San Francisco, Sassy knocks a flower pot off of a shelf on top of one of the mean stray dogs.
At the beginning of the 1998 film version of The Avengers (not that one), Steed is almost hit by a flowerpot that drops down from a window above him.

Literature

Dandelion in The Witcher saga was flower-bombed by his current mistress breaking with him, after she threw all his possessions out of the window.

Live Action TV

In Dream High, Baekhee drops a flower pot from the top of the school building, hoping to hurt Hyemi. She hits Samdong instead and he is rushed to the hospital for a serious head injury.

Music

In "Pray For You" by Jaron & The Long Road To Love, the narrator goes to church and takes away the lesson that instead of hating, you should pray for people. In addition to other misfortunes he wishes on the person he's mad at, he prays a flowerpot will fall from a windowsill and hit them in the head.

Newspaper Comics

Garfield has used this a few times:

Tabletop Games

The homebrew Falling Anvil discipline for Dungeons and Dragons (versions 3.X) includes this in varying degrees, starting with flowerpots, and ranging upwards through anvils, safes, and finally Viking longboats. Of course, it also includes a wide variety of other toon-like attacks and defenses.

Video Games

One of the hazards faced in the Crazy Climber arcade game.
There is a Video Game named "Crackpots" where your goal is to drop flower pots to hit the climbing invertebrate.
A common danger in the Who Framed Roger Rabbit? game, oddly capable of a One-Hit Kill when Eddie comes close.

Western Animation

Every My Little Pony: Friendship Is Magic episode involving "Pinkie Sense" has used this:
- In Feeling Pinkie Keen, when the already horribly-injured Twilight Sparkle is assuring Spike that something is not going to fall, a flowerpot then crashes on her head. Then an anvil. Then a hay wagon. Then a grand piano. They all turned out to have fallen out from a delivery truck that Derpy Hooves was working at.
- In The Mysterious Mare Do Well, during The Reveal that Mare Do Well is some of the Mane 6 teaching Rainbow Dash a lesson, Pinkie Pie says she stopped the building collapse with her Pinkie Sense. She then detects a falling flowerpot with it, and dashes away to avoid it.
- In It's About Time, when Twilight asks the gypsy Pinkie Pie if she can use her Pinkie Sense to detect what will happen in the future, Pinkie explains that it's only for immediate emergencies. Cue flowerpot to Twilight's head.

Pinkie: Like that. (pause) Where did that even come from?

On the Tex Avery short "Bad Luck Blackie", a flowerpot is the first thing that falls on the bulldog's head. Larger and more unlikely objects soon follow.
In the Donald Duck cartoon "Donald's Dilemma", a flowerpot falling on Don's head gives him Identity Amnesia and a handsome voice, making him think he's a great singer. Daisy brings him back to normal by dropping another pot on his head.
On Teenage Mutant Ninja Turtles this happens to poor Michelangelo.