Zig-Zag Stitch Join Crochet Squares & Seams – Photo Tutorial

Zig-Zag stitch is a quick, stretchy method for joining crochet squares, motifs and seams together. It’s really easy to sew.

Here’s what I cover in this blog post:

When to Use Zig-Zag Stitch Joins
How to Join Crochet with Zig-Zag Stitch
Anatomy of a Crocheted Square – learn what bit joins to what

When to Use Zig-Zag Stitch Joins?

If panels, squares or motif edges are the same colour as the joining yarn (a contrast colour will be seen and it isn’t that neat).
When you need a stretchy seam. Think garments that are lacy and don’t need a very neat join. I don’t think this seam is neat or tight enough for joining squares and motifs.
If you are lacking in sewing confidence. This is an easy stitch to sew.

Here’s a close up of a zig-zag stitch join. The two at the top were zig-zag stitched with the same yarn the squares were crocheted in. The two at the bottom were zig-zag stitched in the same yarn, but in a contrast colour.

Two sets of pink crocheted squares showing difference between whip stitch join in same and contrast colour yarn.

how to Join Crochet with Zig-Zag Stitch:

Two pink crocheted with contrast yarn threaded to needle.

Join 1 Step 1 – Identify ‘right sides’ of crochet. Cut a length of yarn 2 x the length of the piece that needs to be joined and thread with a tapestry needle.

Two pink crocheted squares with right sides facing.

Join 1 Step 2 – Place right sides of squares together so wrong sides are facing out.

Two pink crocheted squares with right sides facing and a tapestry needle through the corner chain.

Join 1 Step 3 – Place needle from front to back through back loop of first stitch of Square 1 (square and loop closest to you).

Two pink crocheted squares with right sides facing and a tapestry needle through the corner chains.

Join 1 Step 4 – Place needle from front to back through back loop of Square 2 (square and loop furthest away from you). Pull through needle and yarn, leaving a 10cm/ 4” tail for weaving in. For squares with a 2 chain corner, both chains need to be sewn at this first stage.

Two pink crocheted squares with right sides facing and a tapestry needle through the next stitches.

Join 1 Step 5 – Place needle from back to front through back loop of next stitch of Square 2 (square and loop furthest away from you).

Join 1 Step 6 – Place needle from back to front through back loop of next stitch of Square 1 (square and loop closest to you).

Two pink crocheted squares with right sides facing and a tapestry needle zig-zag stitching the seams together.

Join 1 Step 7 – Continue to zig-zag stitch through the back loops of squares 1 and 2 until all stitches of both edge have been sewn together.

Two pink crocheted squares seamed using zig-zag stitch.

If you have two chains at the corner of each square, only one chain on each side should be joined. See the section of ‘Crochet Square Anatomy’ if you need more detail. Every 4cm or so, pull the two yarn ends together to ‘zip up’ the zig-zag stitches.

Four pink crocheted squares being zig-zag stitched together.

If you are joining more squares, simply work through Steps 1 – 7 with the next two squares, using the same yarn that is attached to the first two squares.

Two photos of four pink crocheted squares being zig-zag stitched together. One photo shows loose joins and the other after tightening.

If there is too much yarn showing between the sets of squares, you can hold the yarn at the top and pull the newly added squares down a little to close the gap. Best done on a flat surface!

Four crocheted pink squares folded over, ready for the second seam join.

Join 2 Step 8 – Repeat Steps 1 – 7 for Join 2 of the four squares.

Four pink crocheted squares with arrows pointing to the unworked corner chain stitches.

The arrows are pointing to the unworked corner chain stitches that need to be zig-zag stitched in Join 2. Note that each of my squares has 11 edge stitches. If you have an even number, the arrows will be pointing in the opposite direction.

Four pink crocheted squares showing where the corner chains are being worked.

This is a close up showing the first two corner chain stitches already joined and the needle through the final two, ready to be joined.

Four pink crocheted squares sewn together with zig-zag stitch.

The finished zig-zag join of four crocheted squares.

Crochet Square Joining Anatomy

If your squares have been crocheted in the round (as a right handed crocheter), the top of your stitches will be leaning slightly to the right.

When you come to join squares together, this can make it tricky to work out which stitch is which, especially at the corner chains. The following annotated photos show you what to look for, so you can make, neat and accurate joins for your crocheted squares and motifs.

If in doubt, always flip to look at the right side of your square, and look for the right lean of the stitch to guide you.

Four pink crocheted squares with lines showing where they are joined.

Four crocheted squares are seamed together using two join lines.

Two pink crocheted squares up close with arrows showing where to sew joins at the corner chains.

A square crocheted in the round would usually have two corner chains. One from each square is used in Join 1 and one from each square will later be used in Join 2.

Four pink crocheted squares up close with arrows showing where to sew joins at the corner chains.

When you are combining four squares, it’s important to recognise which corner chains will be used in which join. If you get it right, your four joined squares will create a neat cross in the centre.

Two photo showing soem zig-zag stitches to join two crocheted squares together.

Prefer a Video Tutorial?

If you would prefer a quick video tutorial, I have one here for you.

Patterns Shown in This Tutorial

Isla Bag uses the crocheted squares shown in this tutorial.