Wool, Cashmere, Merino or Alpaca? A Simple Guide to Sweater Fabrics
Sweater shopping can get confusing fast. One knit is "100% merino," another is "cashmere blend," another is "alpaca and wool," and the prices range from very cheap to very expensive. Which one is actually worth it?
Here is a simple guide to the most common sweater fabrics, what they are good at, and how to take care of them so they last.
Wool (regular sheep's wool)
What it is: The classic. Fiber from sheep, usually a thicker fiber than merino.
Good at: Warmth, durability and holding its shape. Wool naturally resists odors and wrinkles, so you can wear it several times between washes.
Downsides: Regular wool can feel scratchy, especially against the neck.
Best for: Coats, chunky outer sweaters and layering pieces you wear over a shirt.
Merino
What it is: Wool from merino sheep. The fibers are much finer than regular wool, which is why it feels soft.
Good at: Softness without bulk. Merino is warm but breathable, so it is comfortable in heated buildings. It's great for layering under blazers and cardigans, which makes it a favorite for modest dressing.
Downsides: Fine merino knits can pill in high-friction spots, like under the arms or where a bag rubs.
Best for: Everyday crew necks, turtlenecks, cardigans and anything you want to wear close to the skin.
Cashmere
What it is: The fine undercoat of cashmere goats.
Good at: It is incredibly soft and very warm for its weight. A good cashmere sweater feels light but keeps you cozy.
Downsides: It is expensive, delicate, and quality varies a lot. Cheap cashmere often uses shorter fibers, which pill quickly and lose their shape.
How to spot good cashmere: The knit should feel dense, not see-through when you stretch it a little. Gently rub the surface. If it pills right away in the store, it will pill much more at home.
Best for: Special sweaters, wraps and scarves.
Alpaca
What it is: Fiber from alpacas, often blended with wool.
Good at: Warmth. Alpaca is known for being very warm, and it has a soft, slightly fuzzy "halo" that looks cozy and luxurious. It is also often a good option for people who find regular wool itchy, because it doesn't contain lanolin.
Downsides: Brushed alpaca can shed a little at first, and the fuzzy texture isn't for everyone.
Best for: Cardigans and statement sweaters for cold days.
Cotton
What it is: Plant fiber.
Good at: Breathable, easy to wash and not itchy at all. Great for spring, fall and people who run warm.
Downsides: Less warm than animal fibers, and heavy cotton knits can stretch out over time.
Best for: Transitional sweaters, cardigans for air-conditioned rooms and everyday knits.
What about blends?
Blends mix fibers to get the best of each. A wool and nylon blend adds durability. A cotton and cashmere blend is soft and less expensive than pure cashmere. Blends with a lot of acrylic or polyester are cheaper but usually pill faster and don't breathe as well.
A good rule: the higher the share of natural fiber, the better a sweater tends to wear and feel over time.
Knit gauge: fine or chunky?
Gauge is how tightly the sweater is knit.
- Fine-gauge knits are thin and smooth. They layer easily and look polished.
- Chunky knits are thick and cozy, best worn on their own or under a coat.
For modest outfits with several layers, fine-gauge knits are the most useful.
How to care for sweaters so they last
- Wash less. Wool and cashmere don't need washing after every wear. Air them out overnight.
- Hand wash or use a gentle cycle with cold water and a wool detergent.
- Never wring. Press the water out, roll the sweater in a towel, and dry it flat.
- Fold, don't hang. Hangers stretch the shoulders.
- De-pill gently with a sweater comb or fabric shaver.
- Store with cedar to protect against moths, especially over the summer.
Which one should you buy?
- If you want one sweater that does everything, choose a fine merino crew neck in a neutral color.
- If you are always cold, try alpaca or a chunky wool knit.
- If you want something special, invest in good cashmere and take care of it.
- If you run warm or hate itchy fabrics, choose cotton or a cotton-cashmere blend.
Find knits I love right now on the Knits page, and check the deals page, where I list real sale prices on sweaters when I find them.
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