Knitting Pleats

pleated detail on cardigan from Debbie Bliss
Debbie Bliss Magazine
Spring/Summer 2009

I’m fond of structured, tailored garments with dressmaker details. Pleats are one of these details that are more tailored than incorporating gathers. Pleats in a knit fabric are not quite as sharp as fabric pleats, but are still worth the effects they give. There are two categories of pleats: knit/purl pleats (mock pleats) and true pleats (slip stitch pleats). Pleats are best knit in light weight to medium weight wool yarn. You want to use a yarn that keeps its shape, and wool accomplishes this beautifully. Pleats add extra weight to a garment, so consider the fiber content; weighty alpaca is not a good choice. Pleats are commonly used in skirts, and in sweaters to form details or draping effects, like in the cardigan featured above. My focus for this post is true pleats.

Knit/Purl Pleats

This group of pleats resemble textured ribbing. A single panel of stitches is repeated across the width of the fabric. Within each panel are interlocking triangles or diamonds of knit and purl stitches. The effect of this arrangement forms a fold at the juncture of each panel. It’s best not to use knit/purl pleats in close-fitting garments, or the fabric will flatten out against the body. Provide enough ease for the folds to occur.

skirt with knit/purl pleats
Knit/purl Pleated Skirt
from Designing Knitwear
Deborah Newton

True Pleats

These are my favourite, because they mimic fabric pleats, and are best worked in stockinette stitch. A knit pleat has three layers: a face, turnback or fold-under, and an underside. Slip stitches are used to create the foldline, to form a crisp pleat. A vertical column of slip stitches are made on every right side row and purled on the wrong side. There are different types of true pleats:

Knife Pleats – All folds of this type of pleat face the same direction, and the face, turnback and underside are the same width.

Accordion Pleats – These are a series of knife pleats that make up the entire width of the fabric.

Box Pleats – A box pleat is a left-facing pleat immediately followed by a right-facing pleat. Box pleats are not as bulky as knife pleats, and are often seen in skirts.

Inverted Pleats – These are often seen alone in the back of a coat. The pleat is decreased on the fold-underside, and underside to come to a point at the top. In planning this type of pleat, decide on its length and the number of decreases.

Kick Pleats – These pleats are generally placed at centre front, centre back, side or goreline. They can either be box or inverted pleats, commonly seen in a narrow skirt, for ease of movement.

knit true pleat swatches

Planning Pleats 

Before calculating the number of stitches for a pleat decide on the number of pleats you want and the width for each pleat. The pleat width (when folded) is multiplied by the stitch gauge, then multiplied by 3 (the three layers) for the total number of stitches, and includes 1 slip stitch and 1 purl stitch for each pleat. Depending on which side you place the purl stitch, the pleats fold to the left or to the right.

Let’s say you want 2 pleats. The pleat width equals 1in and the gauge is 5 sts/in; therefore each pleat is 5 sts (width of 1 pleat) x 3 (face, turnback, underside) = 15 sts/pleat. 15 sts/pleat x 2 pleats = 30 sts for each pleated section.

Knitting Pleats

The swatch below is made of 2 pleats, each 15 stitches wide, with one folding to the right, and the other to the left. The first image shows the set-up for the pleats, using markers to separate each pleat. The one on the right folds to the right and the one on the left folds to the left. (Set-up row for my swatch – cast on 42 sts. Row 1 (RS): k4, PM; k5, p1, k4, sl 1, k4; k4, PM: k4, sl 1, k4, p1, k5; k4.)

setting up pleat placement
Pleat placement.
making right-facing pleat - closing
Closing right-facing pleat.
working across to next pleat to be closed
Working to next pleat closing.
closing left-facing pleat
Closing left-facing pleat.
finished pleats
Finished pleats.
back side of knit pleats
Back side of knit pleat swatch.

If you are continuing to work the body of the piece above the pleats, you simply want to close the pleats. In my swatch with right side facing: work to first marker for right-facing pleat, slip next 5 sts to dpn for back of pleat, slip following 5 sts onto second dpn for inner pleat, fold over to form pleat at the back of left needle; taking 1 st from each needle [k 3 tog]5 times. Work to next pleat placement. For left-facing pleat: slip next 5 sts onto first dpn for front of pleat, slip following 5 sts onto second dpn for inner pleat and fold to form pleat with dpn’s held in front of work; taking 1 st from each needle [k 3 tog]5 times. Continue to work body in pattern.

Although not commonly done, if you are knitting a garment with true pleats covering the width of the fabric, you may want to bind off the pleats instead of closing. I won’t go into the method of binding off, but it requires you to align the needles the same way as for closing pleats.

Knitting pleats is a little finicky, but is well worth the effort. Closing pleats is similar to working a 3-needle bind off, but with an extra needle, working three stitches together instead of two. Why not add this lovely detail to your next project.