Prism Cascade Corner-to-Corner Afghan: A Free Crochet Pattern for a Rainbow Masterpiece

Are you ready to transform a simple ball of yarn into a stunning, vibrant work of art? The Prism Cascade Corner-to-Corner Afghan is more than just a blanket; it's a journey through a rainbow. Using the popular corner-to-corner (c2c) technique, you'll watch as a mesmerizing gradient of red, orange, yellow, green, blue, indigo, and violet flows diagonally across your hook, creating a dense, textured, and utterly cozy masterpiece. This pattern is designed for the intermediate crocheter who is looking for a rewarding project that is both meditative and visually spectacular. Whether you're an experienced maker or a confident beginner ready for a challenge, this afghan will brighten your home and warm your heart.

Materials Needed: Gathering Your Rainbow

Before you begin your colorful adventure, ensure you have all the necessary supplies. The beauty of this project lies in its simplicity—just seven shades of worsted weight yarn and a single hook.

• Yarn: Worsted weight yarn in 7 colors: Red, Orange, Yellow, Green, Blue, Indigo, and Violet. You will need approximately 300g of each color (total ~2100g).
• Border Yarn: A small amount of white worsted weight yarn for the final border.
• Crochet Hook: 5.5 mm (I-9) crochet hook.
• Other Tools: Yarn needle for weaving in ends, scissors.

Gauge: 4 c2c blocks = 4 inches (10 cm) square. (Note: Gauge is important for size, but since this is a blanket, a slight variation won't ruin the project.)

Step-by-Step Instructions: Building Your Prism Cascade

This afghan is worked diagonally from one corner to the opposite corner. We will start by increasing the number of blocks per row until we reach the widest point, and then we will decrease until we have a perfect square. Let's break it down.

Understanding the C2C Block

Every "block" in this pattern is a tiny cluster of stitches. This is the foundation of the entire afghan.

• Block: Ch 3 (counts as first dc), then 3 dc in the same ch-3 space.
• Ch-3 Space: The space created by the ch-3 at the start of each block.

Abbreviations

Here are the abbreviations used in this pattern:

• ch: chain
• dc: double crochet
• sl st: slip stitch
• st: stitch
• sk: skip
• c2c: corner-to-corner

Starting the Foundation (Row 1)

Let's begin at the very first corner of your afghan.

1. Ch 6.
2. Dc in the 4th ch from hook. (The first 3 chains count as your first dc).
3. Dc in the next 2 ch. You have just created your first block (the bottom-right corner of your afghan).

Row 2 (Increasing)

Now we will add a second block to create the second row.

1. Ch 6. This creates the base for a new block.
2. Dc in the 4th ch from hook, dc in the next 2 ch. This is your first block of Row 2.
3. Turn your work.
4. Sl st into the ch-3 space of the first block from the previous row (the one you just made in Row 1).
5. Ch 3, 3 dc in the same ch-3 space. This is your second block of Row 2.

You now have 2 blocks in this row. Notice how the work is forming a diagonal line.

Row 3 (Increasing)

We will continue to add one block per row. This is the standard c2c increase pattern.

1. Ch 6, dc in the 4th ch from hook, dc in the next 2 ch. (First block of Row 3).
2. Turn.
3. Sl st into the ch-3 space of the first block of the previous row.
4. Ch 3, 3 dc in the same space. (Second block).
5. *Sl st into the next ch-3 space of the previous row, ch 3, 3 dc in that space.*
6. Repeat from * to * across the row. You should now have 3 blocks in this row.

Continuing the Increase & Color Sequence

Repeat Row 3, adding one block each row. You will continue this until you have 20 blocks across the widest part of the diagonal. This is the heart of the rainbow effect. Follow this color sequence for each row, changing colors at the start of each new row:

• Rows 1-3: Red
• Rows 4-6: Orange
• Rows 7-9: Yellow
• Rows 10-12: Green
• Rows 13-15: Blue
• Rows 16-18: Indigo
• Rows 19-20: Violet

Pro-Tip: When changing colors, simply fasten off the old color and join the new color with a sl st in the next ch-3 space, or carry the yarn up the side if you prefer to weave in fewer ends.

Beginning the Decrease

Once you have 20 blocks in a row, the fun part begins—creating the second half of your square. You will now decrease by one block on each row.

1. To decrease at the beginning of a row: Sl st across the first block (3 sl sts) to reach the next ch-3 space.
2. Ch 3, 3 dc in that space. This is your first block of the row.
3. Continue across the row as normal, working a block in each ch-3 space.
4. At the end of the row, do not make the last block. Instead, turn and begin the next row with a decrease (as in step 1).

Continue decreasing in this manner until you have only 1 block left. Fasten off and weave in all your ends.

Adding the Finishing Touch: The Border

A clean, crisp border frames your colorful work beautifully.

1. With your white yarn, join with a sl st anywhere along the edge of the afghan.
2. Round 1: Work a round of single crochet (sc) around the entire afghan. In each corner, work 3 sc in the corner stitch. On the diagonal edges, work approximately 3 sc per block (1 sc in each dc and 1 sc in the ch-3 space).
3. Round 2: Work another round of sc, again placing 3 sc in each corner. Fasten off and weave in all ends.

Your Prism Cascade Afghan is complete! Lay it flat to admire the beautiful gradient you've created. This is a project to be proud of—a true testament to the beauty of simple stitches worked with intention. Enjoy your new, cozy, rainbow masterpiece!