technique: choosing a substitute yarn

6/14/2013 by Sandra McIver

This tutorial is designed to help you choose a substitute yarn that will behave the most like the yarn I used in the book, so that you can get the expected result – a Swirl with the look, drape and feel of the original. Along with choosing the appropriate size, substituting yarns can have the biggest impact on how your Swirl fits. Knitters are often nervous about choosing a substitute yarn, but making a good yarn substitution decision is easy if you follow these four steps:

Step 1: Determine the weight of the original yarn.

Weight is the key factor in choosing a substitute yarn. The stitches-per-inch ratios suggested by yarn companies and terms like lace, fingering, DK, worsted etc offer us some indication of yarn weight, but they can be misleading when it comes to choosing an appropriate substitute yarn. Weight defined by yards-per-gram­ is a much more reliable way to compare one yarn to another.

Review the Materials listing at the front of your Swirl pattern to identify how many yards and grams there are in one skein of the yarn originally used in the pattern. Divide the number of yards by the number of grams to come up with a yards-per-gram figure for original yarn.

(Note: The Materials list in each pattern has two sections. The top portion describes the yarn(s) used in generic terms, i.e. “Single-ply, worsted weight silk” followed by the yardage required per size. The lower portion describes the specific yarn(s) used in the original garment and incudes brand name, yarn name, fiber content by percentage, and the weight and yardage per skein.)

Step 2: Consider the resilience of the original yarn(s).

Different fibers have different degrees of resilience (memory, elasticity)—the ability to stretch and then return to original form.

Check the Materials listing in your pattern again and identify the fiber content of the original yarn. Then take a few minutes to think about the resilience of those fibers and what that tells you about the resilience of the original yarn. Keep in mind that when two or more fiber types are blended to create a yarn, the resulting yarn will usually be less resilient than a yarn made entirely from the most resilient of the fibers in the blend, and, conversely, more resilient than a yarn made entirely from the least resilient of the fibers in the blend.

If you are not confident about your fiber knowledge, your favorite Local Yarn Store (LYS) can help guide you, or pick up a copy of Clara Parkes’ (of Knitters fame) book The Knitter’s Book of Yarn. But if that isn't practical, here’s a little summary that covers the fiber types used in knit, Swirl!:

  • 100% wool (of any type) will have the most resiliency. Often the springy elasticity of wool is apparent in the skein before knitting. Pinch a length of wool at least 8 – 10 inches long between the fingers of each hand and pull your hands away from each other. Notice how much the yarn stretches and then returns to the original length when you relax your hands again.
  • 100% silk will have the least resiliency. Clara Parkes, in The Knitters Book of Yarn, describes silk as having “slow elasticity…it’ll definitely stretch, but it’s slow to recover and may not quite make it back to the original shape.”
  • In between the two extremes, we have (listed in descending order from most resilient to least resilient):
    • Blends of wool (50% and higher) with other types of fiber
    • cashmere
    • alpaca
    • mohair
    • Blends without wool

(Note: For purposes of this tutorial, I address only protein fibers used in Knit, Swirl! I have not used 100% cellulose fiber yarns (cotton, linen, hemp) or any yarns containing cellulosic fiber (rayon, bamboo, Tencel) in my Swirl designs because of the innate inelasticity of these fibers. Yarns that are blends of wool and a low percentage of cellulose or cellulosic fibers can be used for Swirls, but the higher the percentage of these fibers, the more unpredictable the results will be. For those who prefer to avoid protein fiber yarns, synthetic fiber yarns (acrylic, nylon and polyester) are resilient and can be used successfully for Swirls; however, because synthetic fiber yarns tend to resist blocking, they may lack some of the drape and fine-tuned shaping that blocking provides.)

Step 3: Review the construction of the original yarn(s).

The manner in which a yarn is spun and plied together can increase or, conversely, tame resiliency. These factors will also make a difference in the look of the finished fabric. Review the brief description of the structure of the original yarn included in the Materials listing.

Step 4: Consider your substitute yarn choices.

Whether you’re pulling from your stash or from the shelves of your local yarn shop:

  • Begin by looking for yarn of the same, or very similar, yards-per-gram as original yarn.
  • Review the chart below (repeated here from technique: measuring gauge tutorial) to help you target yarns most like the original.
  • Once you’ve assembled a few choices based on weight, consider the fiber content of your selections with an eye toward identifying yarns that are likely to have a similar degree of resilience.
  • Finally, consider construction of your substitute yarn. If it is significantly different from the original (a boucle vs. a lightly twisted single-ply for instance), it’s likely not a good choice.

Chart of Yarn Characteristics


Swirl Pattern

Yarn Characteristics

Note: Behavior of the yarn in a properly knit swatch trumps actual fiber content.

Category 1

High Resilience

Winter Waves
Coat of Many Colors

  •  Usually, but not always, 100% wool or mostly wool. Example: Coat of Many Colors uses a 55% mohair/45% wool yarn that should belong in Category 2, but has the behavior in a swatch of Category 1 (see note at top of chart).
  •  Some acrylics engineered to behave like wool will work.

Category 2

Moderate Resilience

Going Green
Mink in Motion
Tangerine Rose
Forest Fiesta
Sophie’s Swirl
Strata Sphere
Plum Perfect
Silhouette in the Sun
Coat of Many Colors in Twizzle

  •  Blends of a high percentage of wool and fiber that subdues the memory and adds some drape – silk, etc.
  •  100% or mostly cashmere or baby/royal alpaca
  •  Behavior is similar to Category 1 because it still has a bit of memory after blocking but doesn't have as much as Category 1 yarns.

Category 3

Relaxed Resilience

Depth of Field
Rubies and Ribbons
Copper Collage
Golden Glow
Wild Thyme
Sheer Beauty

  •  Usually a combination of yarns of different weights, fiber content and texture.
  •  Main yarn usually at least 50% silk.
  •  Some rayon type fibers may work as substitutes for silk in this category.
  •  The behavior of this Category is very different from Categories 1 and 2 as the swatch will have little memory.

Category 4

Low Resilience

Silken Dreams

  •  100% silk with beads


A great resource for researching yarn substitution possibilities is  Their website database is extensive and they make an admirable attempt to keep it up to date.  Enter the original yarn name in the search box and up pops a list of yarns that are comparable in gauge, fiber content, yarn construction etc.  They even go so far as to give percentage ratings to the exactness of the match. 

Step 5: Buy ONE skein and knit a swatch!

I know, I know. Nobody wants to knit a swatch. But a swatch isn't just about gauge. It's about the fabric you are going to make while you are knitting your Swirl. You can “get gauge” in almost any yarn but are you actually going to like the fabric? Will a Swirl in that fabric look, drape and feel like the original?

Before you cast on that swatch, though, please take a moment to read through the tutorial technique: measuring gauge in a Swirl.

Text and illustrations copyright © 2013 Sandra McIver