How to block knitting and crochet
Blocking is the finishing step that makes stitches even, edges straight and squares the same size. Here's how to do it for every fibre.
Updated
Which method for which fibre
| Fibre | Method | Notes |
|---|---|---|
| Wool, alpaca, other animal fibres | Wet block or steam | Blocks beautifully and holds its shape. Lace opens up dramatically. |
| Superwash wool | Wet block, gently | Can grow when wet: support the weight, don’t stretch, and pin to measurements. |
| Cotton, linen, bamboo | Wet block or steam | Evens out stitches well; can stretch lengthways, so dry flat. |
| Acrylic | Spray, or steam held above | Never press an iron on it. Steam relaxes (“kills”) it permanently, so test on a swatch first. |
| Blends | Treat as the most delicate fibre | A wool–acrylic blend blocks like acrylic: spray or careful steam. |
Always check the ball band: it tells you whether a yarn can be washed, how hot, and whether it can be ironed.
Wet blocking
- Soak the piece in lukewarm water, with a little wool wash if you like, for 15–20 minutes until it's wet through.
- Squeeze out the water gently, never wringing. Roll it in a towel and press to take out more.
- Lay it flat on blocking mats or a towel, ease it to the size and shape you want, and pin the edges every inch or two.
- Leave it to dry completely before unpinning.
Spray blocking
Pin the dry piece to shape, then mist it evenly with water until it's damp all over. Leave it to dry. This is the gentlest method, good for acrylic and for pieces you don't want to grow.
Steam blocking
Pin the piece to shape, then hold a steam iron just above it, letting the steam go into the fabric without the iron touching it. Let it cool and dry before unpinning. Quick for wool and cotton; use it carefully on acrylic.
Blocking squares to the same size
- Draw or mark a template of your square size on a blocking mat (many mats have a grid), or push pins in at the four corners as a guide.
- Block several at once, pinning each to the same marks. Squares made at the start and end of a project often differ; blocking evens them out.
- Join once they're dry, then give the finished blanket a final light block to settle the seams.
Common questions
Do I need to block my knitting or crochet?
Not always, but it helps almost everything. Blocking evens out stitches, straightens edges, opens up lace and lets you set the final size. Blankets made of squares or strips join far more neatly after blocking.
Can you block acrylic yarn?
Yes, but gently. Mist it with water and let it dry pinned out, or hold a steam iron just above the fabric without touching it. Steam changes acrylic permanently, making it drapier, so try it on a swatch first.
What do I need to block?
Something flat you can pin into (foam blocking mats, a spare bed or a towel on a carpet), rust-proof pins, a spray bottle or steam iron, and a tape measure. Blocking wires make long straight edges much easier.
How long does blocking take?
As long as it takes to dry: usually a few hours for spray blocking and up to a day or two for a wet-blocked blanket. A fan or a warm (not hot) room speeds it up.