Flower with Petal Function

By the end of this lab you'll be able to:

• Define a function that draws one petal and call it multiple times
• Pass parameters to a function to control size and color
• Use rotation between function calls to assemble a symmetric flower

Eight petals — each a pair of arcs — radiate from the center, cycling through warm pink and magenta tones to form a blooming flower.

Welcome to the Flower with Petal Function!

In this lab you'll write a petal() function once and call it 8 times. That's the power of functions — write it once, reuse it forever! Let's code it together!

How the Flower Works

The petal(size, color) function draws one petal using two circle() arcs facing opposite directions. After each petal, the turtle rotates 45° so the next petal points in a new direction. 8 petals × 45° = 360° — a full flower.

Sample Code

import turtle
monty = turtle.Turtle()
monty.speed(0)
monty.hideturtle()

def petal(size, color):
    monty.color(color)
    monty.begin_fill()
    monty.circle(size, 60)
    monty.left(120)
    monty.circle(size, 60)
    monty.left(120)
    monty.end_fill()

colors = ['hotpink','deeppink','magenta','orchid',
          'hotpink','deeppink','magenta','orchid']

for i in range(8):
    petal(80, colors[i])
    monty.left(45)

What Do You Think Will Happen?

The loop calls petal() 8 times, rotating 45° between each call. 8 × 45° = 360°. How many petals will appear in the finished flower? Make your guess — then click Run to find out!

Try It Now

▶ Run ↻ Reset

Exactly 8 petals, one per call. Were you right?

How It Works

monty.circle(size, 60) draws only a 60° arc of a circle — the second argument is the arc angle. Two 60° arcs facing opposite directions form a leaf-shaped petal. The two left(120) turns are the geometry that closes the petal back at the starting point.

The def petal(size, color): function definition happens once before the loop. Inside the loop, petal(80, colors[i]) is the call — it runs all the code inside the function with size=80 and color=colors[i].

Explanation Table

Line	What it does
def petal(size, color):	Define a reusable petal-drawing function
monty.circle(size, 60)	Draw a 60° arc of a circle of the given radius
monty.left(120)	Turn to face the opposite arc direction
petal(80, colors[i])	Call the function with specific size and color
monty.left(45)	Rotate 45° so the next petal points in a new direction

Learning Check

Your Turn — Add the Rotation

The program below draws 8 petals but they all point in the same direction — all stacked up! Add one line inside the loop, after calling petal(), to rotate 45° before the next petal.

▶ Run ↻ Reset

The missing line is monty.left(45) — 8 petals × 45° = 360°, a complete flower.

Experiments

1. Change the petal count. Use range(6) and monty.left(60). You'll know it worked when 6 petals form a simpler flower shape.

2. Make larger petals. Call petal(120, colors[i]) instead of petal(80, ...). You'll know it worked when the petals extend further from the center.

3. Use a green stem. Before the loop, add monty.color('green'); monty.pensize(4); monty.goto(0, -150); monty.penup(). You'll know it worked when a thick green line appears below the flower.

4. Add a yellow center. After the loop, add monty.penup(); monty.goto(0, -20); monty.dot(40, 'yellow'). You'll know it worked when a yellow circle appears at the center of the petals.

Beautiful Work!

You wrote your first parameterized function and called it in a loop — that's the foundation of all reusable code in programming! Up next: Honeycomb Grid to see functions and tiling in action.