Made and counted by Wren —

Coastal blue granny square patchwork cardigan pattern

5.5mm hook, worsted weight yarn builds a granny square patchwork cardigan in three colors.

IntermediateLevel

8-12 hoursTime

5.5 mmHook

WorstedYarn

Jump to the pattern

About this pattern

A granny-square patchwork cardigan worked in Dusty Blue, Cream, and Taupe worsted weight yarn with a 5.5mm hook. Each square finishes at 5.5 inches by 5.5 inches after blocking. Yardage runs 600-850 yards for Color A, 400-550 for Color B, and 300-400 for Color C depending on size. A yarn needle, stitch markers, and blocking mats support assembly and shaping into the finished garment.

This cardigan builds from classic granny squares, worked in Dusty Blue, Cream, and Taupe and joined into a patchwork panel. Each square measures 5.5 inches by 5.5 inches after blocking, so the finished chest and sleeve dimensions hinge on how many squares get stacked and seamed. Worsted weight yarn held with a 5.5mm hook keeps the clusters open and clearly defined, letting the three colors read as distinct blocks rather than blending. Yardage splits across three size ranges per color, so square count tracks the size chosen rather than a single fixed total.

Skill level: Beginner to Intermediate. You should be comfortable working in the round, changing colors, basic seaming techniques, and following a simple construction layout. If you have never made a granny square before, practice a few small ones first; once you have the rhythm down, the rest of this cardigan is smooth sailing.

The open front design skips buttonholes and zippers entirely, so the cardigan simply slips on over a tee or turtleneck. Wide bell sleeves add a bohemian feel, and scalloped edging along the front and hemline finishes the look.

The pattern

Written out round by round

Materials

Yarn

Worsted weight yarn (weight category 4)
Color A (Dusty Blue): 600 (700, 850) yards
Color B (Cream): 400 (450, 550) yards
Color C (Taupe): 300 (350, 400) yards
Recommended fiber: a soft acrylic blend or a machine-washable wool for easy care; choose yarn with good stitch definition to show off the granny stitch clusters.

Hook

5.5mm (US I/9) crochet hook, or size needed to obtain gauge

Notions

Yarn needle for weaving ends and seaming
Stitch markers
Scissors
Blocking mats and pins (optional but recommended)
Gauge
One classic granny square using the pattern below should measure 5.5 inches by 5.5 inches after blocking.
Always check your gauge before starting. If your square is too small, go up a hook size. If it is too large, go down a hook size. Gauge matters for wearables because it affects the final fit.

Abbreviations

ch = chain: Wrap yarn over hook, pull through loop on hook. This creates a foundation or a space.
sl st = slip stitch: Insert hook, yarn over, pull through both loops at once. Used for joining rounds.
dc = double crochet: Yarn over, insert hook, yarn over and pull up a loop (3 loops on hook), yarn over and pull through 2 loops (2 loops remain), yarn over and pull through remaining 2 loops. Creates a tall stitch.
sc = single crochet: Insert hook, yarn over and pull up a loop (2 loops on hook), yarn over and pull through both loops. A short, dense stitch.
3-dc cluster = three double crochets worked into the same stitch or space. This is the building block of the granny square.
ch-sp = chain space: The gap created by a chain in the previous row or round.
RS = right side: The front or public-facing side of your work.
WS = wrong side: The back or inside of your work.

Classic Granny Square Pattern

Pattern Notes

1. All granny squares are worked in the round from the center outward.

2. Join each round with a slip stitch to the top of the beginning chain-3 (which counts as your first double crochet).

3. Color changes happen at the end of rounds. Fasten off and join the new color with a slip stitch in any corner space.

4. Block all squares before assembly. Trust me on this. It makes seaming so much easier and gives a professional finish.

5. The front panels, back panel, and sleeves are assembled separately, then joined at the shoulders and sides.

Step-by-Step Crochet Pattern Classic Granny Square (Make Multiple)

You will need the following number of squares based on your size: S/M - 36 squares; L/XL - 42 squares; 2X/3X - 48 squares.

This includes squares for the body and sleeves. I will break down placement in the assembly section.

Round 1Color A or C, varies by placement Ch 4, sl st to first ch to form a ring. Ch 3 (counts as first dc here and throughout), 2 dc into ring, ch 2, *3 dc into ring, ch 2* three times, sl st to top of ch-3 to join. (4 clusters, 4 ch-2 corner spaces)

Round 2Color B Join Color B in any corner ch-2 space. Ch 3, 2 dc, ch 2, 3 dc all in same corner space (first corner made). *Ch 1, skip to next corner ch-2 space, work (3 dc, ch 2, 3 dc) in corner space (corner made)* three more times, ch 1, sl st to top of ch-3 to join. (8 clusters, 4 ch-2 corners, 4 ch-1 side spaces)

Round 3Color A Fasten off Color B. Join Color A in any corner ch-2 space. Ch 3, 2 dc, ch 2, 3 dc in same corner space. *Ch 1, 3 dc in next ch-1 space, ch 1, (3 dc, ch 2, 3 dc) in corner ch-2 space* around. End with ch 1, 3 dc in last ch-1 space, ch 1, sl st to top of ch-3 to join. (12 clusters total, 4 corners, 8 side clusters)

Round 4Color B Fasten off Color A. Join Color B in any corner ch-2 space. Ch 3, 2 dc, ch 2, 3 dc in same corner. *Ch 1, 3 dc in each ch-1 space along side, ch 1, (3 dc, ch 2, 3 dc) in corner* around. Sl st to top of ch-3 to join. Fasten off. (16 clusters total, 4 corners, 3 side clusters per edge)Weave in ends. Block square to 5.5 inches.

Color Variations

Looking at the finished cardigan, I can see some squares are worked primarily in dusty blue with cream accents, while others feature more taupe. Here is how to create visual variety:

Variation 1 (Blue Dominant): Rounds 1 and 3 in Color A (Dusty Blue), Rounds 2 and 4 in Color B (Cream)

Variation 2 (Taupe Accent): Round 1 in Color C (Taupe), Rounds 2 and 4 in Color B (Cream), Round 3 in Color A (Dusty Blue)

Variation 3 (All Blue): All rounds in Color A with Color B only on Round 4

Mix and match these variations across your squares to create the patchwork effect shown. There is no exact formula. Trust your eye and lay them out before seaming to make sure you like the arrangement.

Assembly: This is where your cardigan comes together. Take a deep breath. It is easier than it looks.

Back Panel: Arrange squares in a grid. S/M - 3 squares wide by 4 squares tall (12 squares); L/XL - 3 squares wide by 5 squares tall (15 squares); 2X/3X - 4 squares wide by 5 squares tall (20 squares).

Joining Method: Hold two squares with right sides facing. Using Color B and your yarn needle, whip stitch through back loops only along one edge. This creates a nearly invisible seam on the right side. Alternatively, you can use a single crochet join: hold squares with wrong sides together and, working through both layers, sc evenly along the edge. This creates a visible ridge on the right side, which adds a nice design element. Join all squares into horizontal strips first, then join strips vertically to complete the back panel.

Front Panels (Make 2): Each front panel is narrower than the back. S/M - 2 squares wide by 4 squares tall (8 squares each, 16 total); L/XL - 2 squares wide by 5 squares tall (10 squares each, 20 total); 2X/3X - 2 squares wide by 5 squares tall (10 squares each, 20 total). Assemble the same way as the back.

Sleeves (Make 2): The sleeves are constructed as flat rectangles, then seamed into tubes. S/M - 2 squares wide by 3 squares tall (6 squares each); L/XL - 2 squares wide by 3 squares tall (6 squares each); 2X/3X - 2 squares wide by 4 squares tall (8 squares each).

Joining Body Pieces: 1. Shoulder Seams: Place front panels against back panel, right sides together. Seam along the top edge for one square width on each side. Leave the center back squares open for the neck. 2. Attach Sleeves: Find the center of the sleeve top edge.

Tester's notes

5.5mm hook sets the stated gauge; change hook size before the first square is joined to others, not after.

Stitch markers placed at the start of each round prevent lost rounds across repeated granny squares.

Tension should stay loose enough that clusters stay open; tight tension pulls finished squares under 5.5 inches.

Color changes between A, B, and C happen at round joins; keep tension consistent across every square so blocking produces uniform 5.5 inch pieces.

Yardage splits 600-850 yards for Color A, 400-550 for Color B, and 300-400 for Color C; weigh remaining skeins against squares left before starting a new color.

Finished measurements for this relaxed, oversized fit: S/M - 44 inch bust, 26 inch length (shoulder to hem), 18 inch sleeve length; L/XL - 50 inch bust, 28 inch length, 19 inch sleeve length; 2X/3X - 56 inch bust, 30 inch length, 20 inch sleeve length.

Work in progress

Coastal blue granny square patchwork cardigan pattern — photo 2

Coastal blue granny square patchwork cardigan pattern — photo 3

At a glance

Rounds	4
Level	Intermediate
Time	8-12 hours
Hook	5.5 mm
Yarn	Worsted

Gauge check

Block one finished granny square flat and measure it: it should read 5.5 inches by 5.5 inches.

If the square comes up smaller, move up a hook size; if it comes up larger, drop down a size before blocking or joining any others.

If something looks wrong

Square measures smaller than 5.5 inches after blocking.: Tension is tighter than the sample; move up to a 6mm hook or loosen the working loop on the next round.
Squares pucker or cup instead of lying flat.: A corner chain space was skipped or worked into twice; check that each corner holds its full chain space before starting the next round.
Color blocks shift position between squares.: Stitch markers were not placed at round starts; mark the first stitch of every round so A, B, and C land in the same spot square to square.
Running short on Color A before finishing all squares.: Yardage estimates (600, 700, 850 yards) assume consistent tension; weigh used yarn against squares completed and reorder before starting the final size's squares.

Yarn substitutions

Cotton, worsted weight	Drape drops and squares stiffen; block firmer and expect yardage to run slightly past the 600-850 yard range for Color A.
Machine-washable wool blend, worsted weight	Closest match to the stated gauge and stitch definition; hook stays at 5.5mm with no yardage adjustment.
DK weight wool or acrylic	Squares shrink below 5.5 inches at the same hook; size up to a 6mm hook or add rounds to reach the target measurement.

Original pattern: https://bunnypatterns.com/coastal-blue-granny-square-patchwork-cardigan-free-pattern/

FAQs

Questions

How many granny squares does this cardigan need?

The pattern does not total a fixed count; yardage ranges of 600-850 yards for Color A, 400-550 for Color B, and 300-400 for Color C scale with size, so square count follows the size chosen rather than one flat number.

Why does gauge matter more here than on a toy pattern?

Squares measuring off from 5.5 inches by 5.5 inches change the final chest and sleeve width once joined, unlike a toy where size drift is cosmetic. Check gauge on one blocked square before committing to the full set.

Should squares be blocked before or only after joining?

Blocking each square to 5.5 inches by 5.5 inches before joining keeps seams even across the patchwork. Blocking only at the end risks squares settling at different sizes if tension drifted across the project.