For when you’re standing in front of the yarn wall genuinely having no idea which one to grab
Here’s a conversation we have at the shop roughly forty-seven times a week.
A customer picks up a gorgeous skein, turns it over in their hands, looks at the label, looks at us, and says: “Is this one good for a jumper?”
And we ask a few questions. Have you got a pattern? Can we have a look? Is this colourwork? Are we doing cables? Are we making this for someone with sensitive skin? And suddenly we’re deep in a conversation about fibre content, and they’re looking at us like we’ve started speaking Elvish.
It’s not Elvish. It’s just yarn. And once you understand what the main fibres actually do, everything gets a lot easier.
So let’s talk about it.
First: Why Does Fibre Even Matter?
Because two balls of yarn can look almost identical on the shelf and behave completely differently on the needles. One might have a gorgeous stretch and spring back into shape after you’ve worn it all day. The other might drape like liquid and never stretch at all, lengthening with every wear. You could knit the exact same pattern with both and end up with two entirely different garments.
The fibre is where all the personality lives. It’s not about one being “better” than another — it’s about understanding what each fibre wants to do, and choosing the one that matches what you’re trying to make.
Cotton: The Reliable Summer Best Friend
Cotton is spun from the fluffy bolls of the cotton plant, which makes it one of the most breathable, washable, and hardwearing fibres out there. Here in Australia, it’s an absolute staple. If you’re knitting something for summer, cotton is usually where you want to start.
What’s it like to knit with?
Cotton has very little stretch. That’s the big thing to know. Wool has this wonderful spring to it that makes it forgiving if your tension wanders — cotton does not offer that same grace. What you knit is what you get.
The flip side is stitch definition. Because there’s no stretch, every stitch sits right where you put it, which makes cotton absolutely beautiful for textured stitch patterns, cables, and anything where you want the detail to read clearly. Your moss stitch will look crisp. Your cables will pop. Nothing gets lost in fuzzy fibres.
It can feel a little heavier on the needles than wool of the same weight, and finished garments often “grow” slightly once blocked and worn. This is why swatching in advance is genuinely non-negotiable with cotton — and not just any swatch. You need to wash it first. Cotton behaves differently to wool when wet; it tends to stretch widthwise but can actually contract in length, which means a swatch measured straight off the needles is telling you almost nothing useful. Wash it, dry it flat, then measure. What you find might surprise you, and it’s a lot better to be surprised by a small square of knitting than by a finished jumper.
Why does cotton feel less stretchy than wool?
Wool fibres have a natural crimp — a tiny wave structure built into each fibre that acts like a spring. Cotton fibres are smooth and straight. No crimp, no spring. That’s the whole reason. It’s not a flaw, it’s just a different personality. Once you know it’s coming, you can work with it beautifully.
Is it good for beginners?
Honestly? It’s not the easiest starting fibre. Because the stitches don’t relax and adjust the way wool does, mistakes sit there looking at you. If you’re just learning, we’d usually point you toward merino wool first — it’s far more forgiving.
But if you’re knitting something for warm weather and wool’s not going to work, you can’t do better than a cool cotton. It’s worth the extra attention to tension for something you’ll actually want to wear in summer.
Great for:
Summer tops and tanks, dishcloths and face cloths, baby garments, anything that needs to breathe. Also anything you want to throw in the machine wash on a warm cycle without drama.
Silk: The One That Makes Everyone Stop and Stare
Silk comes from silkworm cocoons, which is either fascinating or mildly alarming depending on your feelings about silkworms. Either way, the result is one of the most beautiful fibres you can knit with.
Pure silk has this unmistakable sheen — it catches the light in a way no other natural fibre does. And the drape. Oh, the drape. Silk moves like water. If you’ve ever wondered why some shawls just seem to flow and others sit more structured, it’s usually down to the silk content.
Here’s the honest truth though: pure silk is expensive, demanding, and genuinely tricky to work with. It takes approximately 5,500 silkworm cocoons to produce a single kilogram of silk — which goes some way to explaining the price tag. And on the needles, it’s more likely to slide off, especially if you’re a loose knitter or using metal needles, and that slipperiness makes it hard to maintain consistent tension. It also has no memory, meaning it can stretch considerably when washed and won’t spring back.
This is why in practice, almost everyone reaches for silk in a blend rather than pure. And honestly? That’s absolutely the right call. A merino-silk blend gives you that gorgeous lustre and drape with enough elasticity to actually enjoy knitting it. Two of our favourites are our own Silken Singles — a beautiful hand-dyed merino-silk that really shows off the sheen — and Malabrigo Silky DK, which has that incredible softness Malabrigo are known for with the added lustre and drape that silk brings. A mohair-silk blend — which is what Knitting for Olive have made so wildly popular — adds that dreamy halo alongside the sheen. And if mohair isn’t your thing (a somewhat inconvenient affliction when you run a yarn store, I’ll admit), Fyberspates Cumulus is a stunning alpaca-silk blend that gives you all that drape and lustre without the halo. You get all the beauty of silk with far less of the frustration.
Great for:
Shawls, wraps, and cowls where you want beautiful drape and movement. Special occasion garments. Anything where you want the yarn itself to be the star of the show.
Wool: The One That Started It All
Wool has been the backbone of knitting for centuries, and there’s a reason it’s still what most people reach for first. It’s elastic, it’s forgiving, it blocks beautifully, and it comes in approximately every weight and colour combination imaginable.
But “wool” is a big umbrella. Let’s break it down by the types we stock and what makes each one special.
Merino
Fine, soft, and incredibly versatile. Merino is the wool that converted all the people who thought they were “allergic to wool” — often they were just reacting to coarser wools, not wool itself. Merino is gentle enough for next-to-skin wear, including babies, and it has beautiful stitch definition without being crisp or scratchy.
There’s a reason merino feels like such a natural choice here in Australia — we’ve been producing some of the world’s finest merino wool for generations. It’s practically in our bones. And if you’re making your first jumper and you’re not sure what to choose, merino in a DK or Aran weight is almost always the right answer.
Superwash Merino
Superwash is merino that’s been treated so it can go in the washing machine without felting. The treatment removes the tiny scales on the wool fibres that would normally lock together and shrink when agitated with heat and water.
Is it exactly the same as untreated merino? Not quite. It’s often slightly less elastic and can be a bit heavier in the hand. And if you’re planning colourwork, it’s worth knowing that non-superwash is actually the better choice — those natural scales make the stitches grip each other and bloom together when washed, creating that beautifully cohesive finish you see in traditional Fair Isle and Scandi colourwork. Superwash will give you crisper, more defined stitches but is less forgiving if your tension wanders.
That said, for anything that needs to be properly machine washable — baby clothes, socks that’ll get worn hard, anything going to someone who absolutely won’t hand wash — superwash is brilliant.
Sock Yarn
Sock yarn is typically merino (or similar fine wool) with nylon blended in — usually around 10–25%. The nylon is there for durability, because pure wool socks would wear through at the heel and toe far too quickly. The result is a tightly spun, hardwearing yarn that’s great not just for socks, but for any project where you need a fine yarn with longevity. Shawls, lightweight garments, colourwork — sock yarn handles all of it beautifully. And the colour range in sock yarns? Absolutely spectacular. Dyers love working with sock weight.
Mohair
Mohair comes from Angora goats, and if you’ve ever picked up a skein of it, you know exactly what it looks like: a halo of incredibly fine, incredibly soft fibres surrounding the twisted core of the yarn, creating this dreamy cloud-like effect.
Mohair is almost always used held together with another yarn rather than on its own — typically a fine merino or silk — because the halo effect is part of the whole point. Brands like Knitting for Olive have made mohair silk blends enormously popular, and honestly, once you’ve knitted with one you understand why. Warm, lightweight, with this soft blurred quality to the fabric that’s genuinely unlike anything else.
One thing to know: mohair blurs stitch definition. Cables and textured patterns will be softened by the halo. For simple stockinette or gentle textures, it’s spectacular. For intricate stitch work where you want everything to read sharply, choose a different yarn.
Alpaca
Alpaca fibre is incredibly soft, incredibly warm, and has this gorgeous drape that sits somewhere between wool and silk. It’s also lanolin-free, which means most people who struggle with wool sensitivities find they can wear alpaca comfortably — it’s as close to hypoallergenic as natural animal fibre gets.
The catch with pure alpaca is that it has less elasticity than wool — those fibres don’t have the same crimp and spring. Which means pure alpaca garments can “grow” quite a bit with wear, especially anything with weight to it like a cardigan. This is why you’ll often see alpaca blended with wool — you get the softness and warmth of alpaca with the structure and memory of wool.
For shawls, scarves, and cowls where drape is a feature rather than a problem, pure alpaca is stunning. For jumpers and cardigans, look for alpaca blends.
Plant-Based Alternatives: Beyond Cotton
Not everyone wants to work with animal fibres, and cotton isn’t always the answer for what you’re making. This is where plant-based alternative fibres come in.
Linen
Linen comes from the flax plant and has this beautiful crisp texture that softens with every wash and wear. Brand new linen can feel quite stiff, but give it time and it becomes one of the most lovely fabrics to wear — cool, breathable, with a slightly rumpled elegance.
We stock Katia’s linen range, which often comes as cotton-linen blends. The cotton adds softness and makes the yarn easier to work with, while the linen brings structure and that gorgeous texture that improves with age.
Linen has minimal stretch, like cotton, but it’s even crisper. Beautiful stitch definition, fantastic for textured patterns, and it washes like a dream. Perfect for summer knits that you want to feel a bit special.
Polyamide (Plant-Based Fibres)
This is the newer player in the yarn world, and it’s worth knowing about. Polyamide fibres can be made from various plant sources — eucalyptus is increasingly common — and they sit in this interesting space between natural and synthetic.
A beautiful example is Queensland Myrtle, which is made from eucalyptus and has gotten the nickname “vegan silk” — and honestly, you can see why. It has that same soft, drapey quality and real lustre that silk is known for, without any of the animal fibre concerns. The feel is smooth and slightly cool to the touch, which makes it brilliant for summer knitting. If you’re looking for something breathable with a bit of elegance for warm-weather tees and tops, this is where we’d point you.
They’re also usually more sustainable in production than conventional cotton, which is worth knowing if that matters to your purchasing decisions.
Blended Yarns: When Two Fibres Are Better Than One
Most of the yarn you’ll find in a good shop is actually blended — a combination of two or more fibres engineered to give you the best qualities of each.
This isn’t a compromise. A good blend is genuinely better than a single fibre for many purposes.
Are blended yarns stronger than pure fibres?
Often, yes. The classic example is sock yarn — wool gives you warmth, softness, and elasticity, nylon gives you durability and resistance to abrasion. Neither one alone is as good for socks as the two together.
Other blends worth knowing about:
Merino and silk brings you the softness of merino with the sheen and drape of silk. Stunning for shawls and lightweight garments. Often easier to work with than pure silk because the merino adds a little grip and elasticity.
Wool and mohair gives you warmth, structure, and that gorgeous halo effect. The wool gives the fabric body, the mohair makes it feel like you’re wearing a cloud. This is the combination you see in so many modern Scandi-style jumper patterns.
Cotton and linen creates something sturdy and beautifully textured. Linen softens with washing and wear, so a cotton-linen blend genuinely gets better over time. Great for structured summer knits that you want to last for years.
Alpaca and wool takes the incredible softness and warmth of alpaca and adds the structure and memory of wool. You get a garment that feels luxurious but doesn’t grow out of shape.
Do Different Fibres Affect How the Stitches Look?
Yes, massively. This is one of the things people don’t always think about when substituting yarns in a pattern, and it’s genuinely important.
Smooth fibres — cotton, silk, linen, and tightly spun wools — show stitch detail clearly. Every twist and cross sits right where you put it. Beautiful for cables, textured patterns, and colourwork where you want every stitch to read.
Halo yarns — mohair especially — soften everything. That blurring effect makes simple stockinette look ethereal, but it will swallow a carefully constructed cable pattern whole. If you’ve spent hours on an intricate lace pattern and can barely see it in your finished shawl, it’s probably the mohair.
Woollen-spun or fluffy yarns sit somewhere in the middle, giving a softer, more rustic look than a tightly spun commercial yarn.
And here’s something that surprises people: the same colour dyed on different fibre bases looks different. Not slightly different — properly different. A “dusty rose” on a merino might look soft and muted. That exact same dye on silk will appear more saturated and jewel-toned because of the sheen. On cotton it might read flatter and more matte.
This is why you can’t just look at a photo online and expect the colour to be identical across different yarn bases. The fibre affects how the dye takes, how light reflects off it, and how the colour reads to your eye. If you’re trying to match colours across different yarns, bring them into the shop so we can look at them together in natural light.
Can the same pattern look completely different in different yarns?
Absolutely. A simple stockinette shawl in silk will drape like water and catch the light at every angle. The exact same pattern in mohair becomes a soft cloud. In cotton, it’s structured and graphic. All from the same set of instructions.
This is one of the genuinely wonderful things about knitting — the pattern is just the blueprint. The yarn is where all the characters live.
Which Fibre is Best for Australian Summers?
This is the question we get most often, and for good reason. Here’s the honest answer:
Cotton and linen are your best bets for real summer heat. They breathe, they wash easily, and they don’t trap warmth against your skin. The Katia cotton-linen blends are particularly lovely for this — the structure of linen with the softness of cotton.
Fine silk or silk-blend yarns work beautifully too if you want something with more drape and lustre — though they tend to need more careful washing.
Fine merino can work in mild weather or air-conditioned environments, but in genuine Adelaide summer heat, it’s not your friend.
Mohair — genuinely, leave it for winter. It is the opposite of what you want in February.
Which Yarn is Best for Beginners?
A smooth, medium-weight merino. Every time.
It grips the needles without being sticky, the stitches are easy to see, and the elasticity means your tension doesn’t have to be perfect to get a good result. If you’re just starting out and someone hands you a ball of fluffy mohair or slippery silk and says “start here” — get a second opinion.
DK or Aran weight merino in a light or medium colour (so you can see your stitches clearly) is the goldilocks zone for learning. Once you’ve got the basics down and your tension is reasonably consistent, the world of other fibres opens up.
The Short Version
Cotton: minimal stretch, brilliant stitch definition, perfect for summer and kitchen knits — and always swatch washed.
Silk: extraordinary drape and sheen, minimal stretch, almost always better in a blend.
Wool: elastic, forgiving, blocks beautifully, and the right answer for most things.
Merino specifically: soft enough for babies, beautiful stitch definition, incredibly versatile — and practically our national fibre.
Mohair: warmth plus halo magic, blurs stitch detail, save it for winter.
Alpaca: incredibly soft and warm, lanolin-free, gorgeous drape, best blended with wool for garments.
Linen: crisp and cool, gets better with age, beautiful with cotton.
Blends: often the best of both worlds, especially where you need specific performance like durability or drape.
And if you’re ever standing in the shop holding two skeins trying to decide — that’s exactly what we’re here for. Come and ask. We’ll help you figure out which one actually makes sense for what you’re making, and we’ll probably end up having a really good conversation about yarn in the process.
Which, honestly, is one of our favourite ways to spend a Tuesday.
Knit On!
Tanya and the Yarn Trader Team
P.S. If you’ve made it to the end of a blog post about fibre properties, congratulations. You’re officially a yarn person. There’s no going back.
P.P.S. Yes, we do stock all of the fibres we’ve talked about here. Come have a feel. Colour matching is best done in natural light, so bring whatever you’re trying to match and we’ll figure it out together.
P.P.P.S. If you’re wondering whether we actually stock mohair given what we said earlier — yes, we do. Lots of it. We’re professionals. We just have our limits.
P.P.P.P.S. Queensland Myrtle. Just go and have a feel. You’ll understand.