Traditional / Public Domain — popular since the mid-1800s
A charming nine-patch variation that adds half-square triangles to four corner positions, creating a block that looks like a stylized insect or fly. Simple enough for beginners but with enough visual interest to make a stunning quilt.
The Shoo Fly pattern appears in quilts from at least the 1850s. The name likely refers to the persistent flies that plagued farm kitchens, and the shooing motion needed to chase them away. It was a popular block for teaching half-square triangles.
Some quilt historians believe the Shoo Fly was used as a signal in the Underground Railroad, though this theory is debated. What is certain is that it was one of the most widely published patterns in newspapers and farm journals of the late 1800s, making it truly a people's pattern.
Also known as: Hole in the Barn Door, Monkey Wrench (sometimes confused), Flock of Geese
finished Block Size
12"
seam Allowance
1/4"
grid Basis
3x3 grid (each unit finishes to 4")
units Required
4 HSTs + 4 squares + 1 center square
All measurements include 1/4" seam allowance unless noted.
| Piece | Fabric | Cut Size | Qty | Notes |
|---|---|---|---|---|
| Center Square | Dark | 4 1/2" x 4 1/2" | 1 | Block center |
| Side Square | Light | 4 1/2" x 4 1/2" | 4 | Top, bottom, left, right positions |
| HST Square | Dark | 5 1/4" x 5 1/4" | 2 | Cut once diagonally for HSTs |
| HST Square | Light | 5 1/4" x 5 1/4" | 2 | Cut once diagonally for HSTs |
Draw a diagonal line on the wrong side of each 5 1/4" light square. Place a light square on a dark square, right sides together. Sew 1/4" on each side of the drawn line. Cut on the drawn line. Press toward the dark. Makes 4 HST units.
Tip: Trim HSTs to exactly 4 1/2" square before assembling the block.
Layout in a 3x3 grid: Row 1 = HST, Light Square, HST. Row 2 = Light Square, Dark Center, Light Square. Row 3 = HST, Light Square, HST. Orient all HSTs with dark triangles pointing toward the center.
Sew the three units of Row 1 together with 1/4" seams. Press seams toward the center unit.
Repeat for Row 2 and Row 3. Press seams in alternating directions for nesting.
Nest seams and sew rows together with 1/4" seams. Press joining seams in one direction.
Press the completed block. It should measure 12 1/2" square. Trim if needed.
See how this traditional pattern looks in different color combinations.
Straight set with sashing strips
Alternating with plain blocks
On point with setting triangles