
It seems that the most popular way to make neat side edges is to slip the first and purl the last stitches of every row. This little trick creates a lovely chain of stitches at each side of the project.
It looks great, but when we need to seam slip stitch edges we have to be careful about the type of seam we use. Because every chain of the edge is formed every other row, basic mattress stitch will create a fairly loose join.
For years, I’ve been using backstitch to join slip-stitch edges, but recently I stumbled upon another type of seam that is as reliable as backstitch but forms a flatter join that also looks lovely on the wrong side of the work.
Let’s see how it works.
If you are a visual learner, click here to watch every step described below in a video tutorial.
SET UP
Because we need to clearly see the slip stitch chains that form the edge, it is a good idea to block the knitted pieces (or at least to steam and even out the edges) before seaming them.
It is especially important for pieces worked in stockinette stitch or a stitch pattern that is based on stockinette stitch. The famous curling of stockinette stitch is quite a pain to deal with when we need to find a leg of a stitch at the very end of that curled edge.
So block the knitted pieces (or at least their edgings) and place two pieces side by side with the right side of the work facing to you.

Now, cut a piece of yarn that is at least twice as long as the future seam and thread that piece of yarn into a wool needle.
If you did a bit of planning and left a long tail when you cast on stitches, use that tail and skip Step 1 outlined below.
To make each step of the seaming easier to understand, I’ll use a piece of yarn in a contrasting colour. But, of course, in real life, it is better to make a seam with the same yarn that you used to knit the project.

STEP 1
First, let’s attach the yarn to the project. You can do it any way you like. I usually simply tie the yarn the bottom of the seam. Here’s how:
1.1. Insert the wool needle from back to front at the very bottom of one knitted piece. Pull it through leaving a tail around 10 cm / 4″ long. Then insert the wool needle from front to back at the bottom of the other knitted piece. Pull the yarn through but not hard enough to take out the tail.

1.2. Tie the yarn and the tail with a square knot.

1.3. Bring the yarn from back to front around the knot to keep the knot at the back of the work.

STEP 2
Now, that we have the yarn in place, it’s time to seam. We’ll always use only one leg of the long stitches at the edge of the fabric – the leg that is closer to the right side of the work.
On the piece at the right side, insert the wool needle from right to left under the right leg of the first edge stitch from the bottom, and from left to right under the right leg of the next edge stitch.

Pull the yarn through.

STEP 3
Now let’s do a mirror version of step 2 on the piece at the left side.
On the piece at the left side, insert the wool needle from left to right under the left leg of the first edge stitch from the bottom, and from right to left under the next edge stitch.

Pull the yarn through.
STEP 4
On the piece at the right side, insert the wool needle from right to left under the right leg of the last stitch that we worked when we run the wool needle through the stitches of this piece.
If you are not sure how to find this stitch, pull the seam a bit sideways and note the last stitch that was seamed. It is the very stitch we are looking for.

Then insert the wool needle from left to right under the right leg of the next edge stitch.

Pull the yarn through.
STEP 5
Now, let’s do the same on the piece at the left side.
First, insert the wool needle from left to right under the left leg of the last worked stitch (the one that’s already been seamed).

Then, insert it from right to left under the left leg of the next edge stitch.

Pull the yarn through.
Repeat steps 4 and 5 until you join all edge stitches of both pieces, or until the seam is as long as you need.

To finish off the seam, insert the wool needle from right to left under the right leg of the last worked stitch at the right side and under the left leg of the last worked stitch at the left side.

Pull the yarn through to join the last worked stitches of both pieces. Then secure the yarn and hide the tails.

As you see, this seam is almost invisible. It works with any stitch pattern. Because we use just one leg of each edge stitch, seaming evens out the stitches that are next to the edge stitches. This solves the only major drawback of slip stitch selvedges – loose stitches at the edge of the work.
In addition to all these benefits, the seam is much flatter than seams formed by mattress stitch and backstitch. And if you look at the wrong side of the work, you will be pleasantly surprised by the look of a neat band formed by chains of stitches.

But that’s not all. I tested this way of seaming to see how it works for joining two bind off edges (to make a shoulder seam, for example) and this technique passed the test with flying colours. The seam is flat and secure with a lovely band of chains of stitches at the back. What a great way to make seams!

If you enjoyed this tutorial,
here’s something else you might find helpful:

“Neat Side Edges” Book
Learn twelve ways to make side edges of a knitted project nice and tidy. Plus, ways to fix side edges, and a way to improve edges of finished projects.
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Binary Socks
-
Brigitte Beret
-
Club 2023
-
Dealing with Unfinished Projects
-
Dictionary of Knitting Symbols and Abbreviations – E-Book
-
Eastern (Russian) Knitting Simplified
-
How to Shape Neckline Without Binding Off Stitches – E-Book
-
Patchwork Knitting
-
Sideways Sweater
-
Sneaker Socks
-
Sock Knitting
-
Zigzag Socks
Happy knitting!
