Frequently I hear from knitters concerned about the appearance of their stockinette stitches. “Stitches are supposed to look like ‘Vs’. Mine look like check marks. What am I doing wrong?” they ask.

Nothing. You’re doing nothing wrong. Really! Let’s figure out why this happens.

Yarns are available in S-twist and Z-twist. Most of our commercially available yarns are S-twist yarn. If you closely examine a strand of yarn, and hold it straight up and down like this |, you notice the twist creates a slanted line in the yarn. You see either a backward slant as found in the letter “S” or a forward slant as found in the letter “Z”.

Let’s look at some S-twist yarns and swatches first. Hold a strand of that yarn askew to mimic the right leg of a knit stitch like this / and observe what happens to the twist. Those slashes line up almost straight up and down. See it? Now hold that yarn askew to mimic the left leg of a knit stitch like this \ and observe what happens to the twist. You see a more exaggerated backward slant. Imagine stacking them, and you can begin to understand the appearance of columns of knit stitches, and why the left and right legs appear different from each other.

Let’s observe this in a few different yarns.

Cascade 220

The first example above is Cascade 220. This wool yarn is an S-twist yarn made of four Z-twist plies. The ply is somewhat relaxed. The left and right legs of the stitches look quite similar. You can see the left legs stack on top of each other looking a little bit like a pole.

Primo Worsted

Above is The Plucky Knitter Primo Worsted. This merino wool/cashmere/nylon blend is also an S-twist yarn made of four Z-twist plies, but it has a tighter twist to it. The right legs of these stitches lean to the right as you’d expect. The left legs actually lean off to the left as well, but they appear not to do so, simply because of the twist. The stack of left legs look like a pole, even more so than the Cascade 220.

Floret

This “pole” effect is even more accentuated in yarn with numerous plies. The Berroco Floret above is a blend of acrylic and cotton. This S-twist yarn is made from five Z-twist plies, and each of those Z-twist plies is in turn made of two S-twist plies. Wow! That’s alotta plies.

Creative Focus Bulky

Now let’s look at a couple of Z-twist yarns. First up is Rowan Creative Focus Bulky, a loose, single ply Z-twist yarn in a wool/alpaca blend. Notice that in this case the “pole” effect occurs on the right legs of the stitches. Interesting, isn’t it?

Silk Garden

At first glance this Noro Silk Garden yarn looks like single ply, but on closer examination it is a loose Z-twist yarn made from two loose S-twist plies. Can you find the slight “pole” effect again on the right legs?

Lima

Finally we have yarn that is neither S nor Z. This is Rowan’s Lima. This yarn is a crocheted chain of very fine alpaca. Its left and right legs looks nearly identical because there is not any twist to the yarn.

Hopefully this clears up a mystery for you. The next time you peruse a knitting magazine or observe your own hand-knits, notice how different yarns behave differently. Accept this as a feature of the yarn and make your yarn selections appropriately. Mostly, accept that there is nothing wrong.