Mattress stitch is the neatest sewn method for joining crochet squares, motifs and seams together. Even with a contrast yarn colour, it’s almost completely invisible!
Here’s what I cover in this blog post:
- When to Use Mattress Stitch Joins
- How to Join Crochet with Mattress Stitch
- Anatomy of a Crocheted Square – learn what bit joins to what
When to Use Mattress Stitch Joins?
- If panels, squares or motif edges are the same or a contrast colour – the joining yarn is near invisible.
- When you need a sturdy join that looks seamless. Particularly great for garments and blankets.
- If you are willing to tackle new sewing techniques. It isn’t as easy as whip stitch, but the results are better!
Here’s a close up of a mattress stitch join. The two at the top were mattress stitched with the same yarn the squares were crocheted in. The two at the bottom were whip stitched in the same yarn, but in a contrast colour.
how to Join Crochet with Mattress Stitch:
Join 1 Step 1 – Identify ‘right sides’ of crochet and place right sides up on a flat surface. The left square is Square 1 and the one on the right is Square 2. Cut a length of yarn 3 – 4 x the length of the piece that needs to be joined and thread with a tapestry needle. There will be yarn wastage, but you need the extra length because the stitches have to be regularly ‘zipped up’.
Join 1 Step 2 – In Square 1, place needle from front to back of back loop of first stitch, then back up through the back loop of the next stitch. I am joining squares together, so am starting with the two corner chains.
Join 1 Step 3 – In Square 2, place needle from front to back of back loop of first stitch, then back up through the back loop of the next stitch. Pull through needle and yarn, leaving a 10cm/ 4” tail for weaving in.
Join 1 Step 4 – In Square 1, place needle from front to back through back loop of the stitch already used.
Join 1 Step 5 – In Square 1, place needle from back to front through back loop of the next stitch.
Join 1 Step 6 – In Square 2, place needle from front to back through back loop of the stitch already used, then through from back to front of back loop of next stitch.
Join 1 Step 7 – Repeat Steps 4 – 6 until all edge stitches have been joined.
Join 2 Step 8 – Every 4cm or so, pinch the yarn at the bottom and pull the yarn at the top to ‘zip up’ the mattress stitches. You may need to slightly open up the last couple of stitches to see where to place your needle next.
Join 1 Step 9 – If you are adding more squares to the seam join, repeat Steps 4 – 5 to incorporate the new left-hand square.
Join 1 Step 10 – Repeat Steps 6 to incorporate the new right-hand square.
Continue to mattress stitch through the back loops of squares until all stitches of both edges have been sewn together. 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.
Join 2 – Repeat Steps 1 – 8 to sew Join 2.
Join 2 – The arrows show the four corner chains that need to be mattress stitched together in Join 2.
Join 2 – Because the mattress stitch is being worked from the right side, when it comes to joining the corner chains the needle needs to go front to back of the already used corner stitch of Square 1, scoop under all of the stitched form Join 1, then from back to front of the new corner chain of the next left-hand square.
Join 2 – Before the corner chains on the right-hand are joined, bring the needle back to the front, between Square 1 and 2. This isn’t between any stitches, just in the gap between the squares. This keeps the right side of the work nice and neat.
Join 2 – Place needle from front to back in back loop of the already used corner stitch of Square 2, scoop under all of the stitched form Join 1, then from back to front of the new corner chain of the next right-hand square.
Join 2 – Keep on zipping up the stitches evert 4cm or so. Finish when all edge stitches have been joined together. Sit back and look at the beauty of your mattress stitch join!
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.
Four crocheted squares are joined together using two join lines.
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.
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.
Prefer a Video Tutorial?
If you would prefer a quick video tutorial, I have one right here for you.
Other Useful Tutorials
- Whip Stitch Crochet Squares, Motifs & Seams is here as a video tutorial, OR here as a photo tutorial.
- Zig-Zag Stitch Crochet Squares, Motifs & Seams is here here as a video tutorial, OR here as a photo tutorial.
Patterns Shown in This Tutorial
- Isla Bag uses the crocheted squares shown in this tutorial.
