Pattern Description:

This is a spiral corner-to-corner (C2C) blanket with a hypnotic swirl effect achieved by working in a continuous color rotation. 

The design gradually increases to five diagonal blocks, then symmetrically decreases, producing a smooth spiral without seams. 

Ideal for gradient or multicolored cake yarn, it creates a balanced and eye-catching throw.

Materials Needed & Measurements:

• Crochet hook: I/5.5 mm (for DK) or J/6.0 mm (for worsted)
• Yarn: approx. 5-9 gradient cake skeins (or 1-3 worsted-weight skeins per color)
• Notions: yarn needle, scissors, measuring tape
• Stitch abbreviations: dc = double crochet, ch = chain, sl st = slip stitch
• Size control: work increases until there are 5 C2C blocks on the diagonal, then decrease symmetrically to form the spiral shape.

Abbreviations Used

• Ch – Chain
• Sl st – Slip Stitch
• Dc – Double Crochet
• St – Stitch
• Sp – Space
• Inc Block – Increase Block (C2C increase)
• Dec Block – Decrease Block (C2C decrease)

Instructions for Making the Spiral C2C Blanket Pattern:

Beginning the Spiral

Starting the First Arm

• Foundation Block:
  • Ch 6.
  • Dc into the 4th ch from the hook and in the next 2 ch.
  • This forms your first block.
• Increase the First Arm:
  • Turn, Ch 6.
  • Dc into the 4th ch from hook and next 2 ch to make a new block.
  • Sl st into the edge of the previous block, then work 3 dc into that edge to complete the join.
  • Repeat until you have 5 blocks making the first diagonal.
• Pause this arm and create the second arm of the spiral.

Building the Spiral Arms

Creating the Remaining Arms

Each arm begins by attaching yarn to the side of the previous arm.

• Join New Yarn: Attach yarn with a sl st to the next exposed edge of the previous arm.
• Work an Inc Block:
  • Ch 6, make 3 dc starting in the 4th ch from the hook.
  • Sl st into the corresponding block edge.
• Continue increasing until the arm also reaches 5 blocks.

Repeat this process for four total spiral arms, each curling naturally around the center.

Shaping the Spiral

Transition from Increasing to Decreasing

Once all arms reach the five-block diagonal, you switch from building outward to shaping the rounded spiral:

• Identify the arm to work next based on the swirl direction.
• Instead of beginning each row with Ch 6, begin with a Dec Block:
  • Sl st across the top of the previous block (3 sl st total).
  • Sl st into the next block.
  • Work 3 dc into the open sp as usual.
• Continue this decrease method whenever you reach the outer edges of the spiral to maintain the curve.

Continuing the Spiral Pattern

Maintaining Rhythm

Each rotation follows a repeating rhythm:

• Increase at inner edges
• Decrease at outer edges
• Work flat (normal C2C blocks) along the sides between inc and dec sections

Continue working around the spiral, adjusting each arm with Inc Blocks or Dec Blocks as needed to keep the spiral smooth.

Finishing the Blanket

• Keep repeating the spiral sequence until the blanket reaches your desired size.
• Finish the final round with only Dec Blocks to close the square cleanly.
• Fasten off and weave in all ends.
• Optional: add a border of single crochet or crab stitch around the edge for stability.