A central double decrease eliminates 2 stitches in a symmetrical way (thus ‘central’ and ‘double’). It results in a strong vertical decrease line that doesn’t slant to the left or the right, the way that the decreases k2tog, ssk, or sl1-k2tog-psso do.
- sl2-k1-p2sso – slip two, k1, pass 2 slipped sts over – central double decrease on the RS
- sl2tbl-p1-p2sso – slip two through back loops, p1, pass 2 slipped sts over – central double decrease on the WS
In the lace pattern shown above (the Bounce Blanket), central double decreases are worked both on RS (right side) and WS (wrong side) rows. So grab the pattern and get started! While these stitches may feel awkward at first, by the time you are done, you’ll have had enough practice to be very comfortable working a central double decrease on either side of the work.
how to sl2-k1-p2sso – slip two, k1, pass 2 slipped sts over – a central double decrease worked on the RS
- Step 1: Slip the next 2 sts at the same time, as if to k2tog, that is, inserting the RH needle tip into the front of the second stitch first, and then the first stitch before slipping these two, at the same time, from the LH to the RH needle
- Step 2: Knit the next stitch
- Step 3: Lift the 2 slipped sts up and over the knit stitch and off the needle
how to sl2tbl-p1-p2sso – slip two through back loops, p1, pass 2 slipped sts over – a central double decrease worked on the WS
Working this decrease is a little trickier, but with a little practice will become easy. In order to slip the stitches through the back loop, you’ll need to turn the work over so you can see the front side of the work, as you are inserting your needle from that side.
- Step 1: Slip the next 2 sts at the same time, from the back of the work, inserting the RH needle tip through the back of the second stitch first, then the back of the first stitch, then slipping the two stitches, at the same time, from the LH to the RH needle (I find I have to flip the work so I can see the knit side in order to do this)
- Step 2: Purl the next stitch
- Step 3: Use the LH needle tip to lift the 2 slipped sts up and over the purl st and off the needle (reach behind the purl stitch, and insert your LH needle tip into the slipped sts on the back / knit side of the work)
We’ve got tutorials that cover a wide range of other knit increases and decreases used in lace patterns:
- yo (yarn over, an increase that creates a hole in the fabric)
- k2tog (knit two together, a right leaning decrease)
- ssk (slip-slip-knit, a left leaning decrease)
- sl1-k2tog-psso (slip 1, k2tog, pass slipped stitch over, a left leaning double decrease)
Or browse our complete list of techniques and in-depth project-based tutorials on our HELP! page. If you’re new to lace, I’d suggest starting with our free pattern, the Gothic Lace Scarf or Cowl, you can learn all the steps in our ‘Let’s Knit Lace’ tutorial.