Tapestry crochet carries an unused strand inside the stitches while another colour works around it. This makes frequent colour changes possible without leaving a long loose strand across the back. The challenge is keeping the carried yarn relaxed enough that the fabric can spread to its intended width.
Stitch terminology: This guide uses US names. US single crochet is UK double crochet; US half double is UK half treble; US double is UK treble. See the full US/UK reference.
Choose a small, high-contrast sample
Use two smooth yarns of similar thickness and compatible care requirements. A light and a dark colour make it easier to see where the change happens. Begin with a modest strip rather than a large bag whose dimensions depend on an unfamiliar tension.
Single crochet is a common starting stitch. Other stitch choices and loop placements can change the alignment and density, so use the stitch specified by the chart you are following.
Change colour on the previous stitch’s final pull-through
If the next stitch should be blue, complete the final pull-through of the preceding stitch with blue. The loop on the hook is then ready for the blue stitch. Waiting until after that next stitch is partly formed can leave an unwanted colour at its top.
Carry the unused colour along the top of the previous row and work around it as instructed. Keep it in a consistent position, rather than letting it wander between the front and back of the fabric.
Try a twelve-stitch block exercise
On a twelve-stitch single-crochet strip, practise three stitches in colour A, three in B, three in A and three in B. Change on the final pull-through before each new block. The count stays twelve; changing yarn does not create another stitch.
If you turn the strip and want the blocks to sit above the same physical colours, the working sequence begins from the opposite edge. Write the return row’s sequence before starting it. This is a simple way to learn chart direction without a complicated picture.
Spread the fabric before adjusting the carried strand
Every few stitches, lay the worked section flat and let it reach its natural width. If the carried yarn is pulling the row inward, release that tension before continuing. Pulling it taut after every colour change can make the strip progressively narrower.
If the unused colour shows through, check stitch placement, yarn contrast and fabric density. Tightening everything aggressively may hide some colour while making the project too rigid or too small.
Keep the yarns from winding around each other
Assign each colour a consistent position beside you and watch the direction in which you switch. Pause to untwist the balls when needed. A controlled setup is more useful than trying to crochet faster through a growing tangle.
For a chart with many large colour blocks, separate bobbins and intarsia may be more suitable than carrying every colour through the entire row.
Measure a colourwork sample
Carrying another strand can change the thickness and gauge compared with plain single crochet. Measure the actual colourwork after the intended care routine. A plain one-colour swatch does not capture the effect of the carried yarn.
Keep a note of the stitch, loop placement, hook and colour-change method. Those details help you reproduce the same fabric when you return to the chart later.
Continue learning
Use separate colour blocks · Review the colour-change movement · Compare one-colour-per-row methods
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