Everything I know about blocking knit and crochet

I’m pretty bonkers for blocking.  It’s magical: stitches smooth out, edges sharpen, pieces lie flat – what’s not to love?  Blocking really gives your work a professional finish and  it’s a heck of a lot easier to sew pieces together when they are all the right shape and size.

***Note: Product mentions are my personal choices and I am not paid to promote them.***

What is blocking?

Blocking is the process of smoothing out and shaping your knit or crochet pieces generally through dampening and pinning in place. 

A bunch of wonky squares ready for blocking!


Do I need to block everything?
Short answer?  No: though it won’t hurt.  I wouldn’t want to try to block an entire afghan, but granny squares?  Sweater pieces?  Definitely.  Openwork stitches like lace must be blocked in order to see the patterns in their full glory.


Can I block any kind of yarn?
Yes, though some yarns block better than others.  Natural fibres like wool, cotton and mohair block like a dream.  Synthetics like acrylic and polyester are a little less responsive to blocking, but can still benefit from the blocking process.  You’ll also want to choose the blocking method best suited to your fibre (see notations below)


3 Methods for blocking knit and crochet

1. How to wet block knit and crochet
BEST USED FOR: Most fibres.

NOT GREAT FOR:  Cashmere, silk, angora, fine-weight single ply yarns, very large pieces like blankets 

PROS: Most effective/transformative blocking method

CONS: Most time-consuming blocking method

Wet-blocking requires completely soaking your knit or crochet piece. This means it’s the most time consuming blocking method as you need to allow time for your piece to air-dry.  Delicate fibres like cashmere, silk and fine-weight, single-ply yarns are vulnerable to breakage when wet, so proceed with caution (or try the steam or spray blocking method).

1.  Fill a bowl (or sink) with warm water and add a dash of wool wash / no rinse wash  if desired. Do not use hot water, especially with animal fibres like wool, which could cause your fabric to felt (or “full”).  Cold water will work fine, it’s just chilly on the hands!

2. Add your knit or crochet piece, ensuring it is  fully immersed.  If concerned about colour bleeding, use separate bowls for each colour.  Avoid moving things around too much when blocking animal fibres as agitation+heat+water= felting.

3. Allow your work to soak for long enough that the fabric is fully saturated.  This can vary from project to project depending on what fibre you use and how dense your stitches are.  I usually leave things to soak while I do other things and it could be hours before I get back to business.  Too long isn’t a problem!


4. Remove your knit or crochet from it’s bath and gently squeeze out most of the water.  Gentle is the key. Don’t wring!  Twisting can be too rough and damage or distort your piece. 

5. Optional: Lay your work on a towel, then roll it up.  Dance on that towel-roll!  Or you know,  just press it firmly.  This technique really gets out most of the water and will speed up your dry-time.

6. Pin your piece to desired measurements and allow to air-dry completely.

2. How to steam block knit and crochet
BEST USED FOR: Natural fibres

NOT GREAT FOR:  Synthetics

PROS: Quick

CONS: Steam can melt acrylic, nylon and polyester

Steam-blocking is a nice speedy blocking method and only requires a conventional iron with a steam setting.  If you have a garment steamer: bonus! Wool and cotton can handle the heat, but be careful with synthetics that could melt: make sure your iron surface doesn’t actually touch your work. Don’t forget to make sure your blocking surface can handle high heat as well.  



Un-blocked square above, blocked square below. Blocking is magic!

1.  Heat your iron to the highest setting with full steam (or fire up that garment steamer). 

2. Pin your dry piece(s) to desired measurements.  

3. Holding your iron a few inches above your work, shoot your piece with a few blasts of steam. If using a garment steamer, hover the nozzle across the piece. Do not touch the surface of the iron or steamer to your work.  The idea is to have the steam penetrate your piece, but not to press or iron it. 

4. If needed, manipulate/re-pin your pieces as needed while they are still warm and damp.

5. Allow your work to completely dry and cool before unpinning 

3. How to spray block knit and crochet
BEST USED FOR: All fibres, including delicates.

NOT GREAT FOR:  Very thick , bulky pieces 

PROS: Gentle

CONS: Less dramatic results

Spray-blocking is the gentler cousin to steam blocking.  This is the method to use if you are using delicate fibres, or unsure of the fibre content of your yarn.

1. Pin your dry piece(s) to desired measurements.  

2. Fill a clean spray bottle with water (cold is fine).

3. Give your piece(s) a good spray until quite damp.

4. Allow your work to completely dry and cool before unpinning


Pinning to Measurements

The blocking process is great for stretching and smoothing your knit or crochet, but how to you make sure your pieces end up the size and shape you want?  “Pin your piece to desired measurements” is a little vague, so here are some tips for shaping up:

•  MEASURE: Use a rigid ruler (wood, plastic, metal) instead of a tape measure  when you can.  Tape measures can twist and distort your measurements 

MARK: If it doesn’t already have one, mark your blocking surface with a grid if possible.  I drew a 1″ /2.5 cm grid on the cork tiles I use for blocking small pieces and it really comes in handy.  Make sure to use a permanent marker or something that won’t transfer to your work. 

STRETCH: The amount of stretching and pulling you want to do before pinning your piece down is up to you.   Most patterns include either a schematic or list finished measurements and hopefully (because you got gauge and didn’t make any mistakes 😉 ) it won’t require too much coaxing to get your piece to match these numbers. Too much stretch can distort stitches and result in a final piece that is far too large.  Delicate fibres are also prone to breakage when wet and too much stress on the fabric could put a hole in your work (ask me how I know).  On the other hand, not enough stretch for certain openwork and lace stitches will result in a less visible stitch pattern.  You can always block your piece a second time and stretch it further if needed.  

PIN: I like to pin down my corners first, then smooth and add extra pins along sides as needed.  If your piece doesn’t have corners (like a doily), pick about 4 spots equally spaced around the exterior edge to start pinning.  Double check your measurements after the initial pins are in place so you don’t have too many pins to move if things aren’t quite right.   Most pins will not hurt or leave a mark in your work, but keep in mind that if you are stretching your piece significantly, enough that the fabric forms a point where it is pinned, your piece will dry to that pointy shape.  If aggressively stretching a piece with a long straight edge, use a LOT of pins to avoid this pin-pointed edge, or maybe try out some Blocking wires (see Blocking materials).

Blocking Pieces to Equal Size
If working a patchwork project, you may have dozens of squares or shapes that all need to be the same size.  You may be tempted to skip the blocking process until all the pieces are assembled, but I find blocking the individual pieces actually makes the assembly process easier.  It’s a lot easier to wet-block a 4″ square than a 50 x 60″ afghan!


Here’s a few tips for blocking multiples of the same shape and size:

• Line ’em up!  Aligning the sides of squares or other straight-sided shapes side-by side means you can check measurements all at once.  If your blocking surface has a grid you’re ahead of the game.

• Stack ’em up! Placing several pieces on top of each other means you can measure and and align all edges and even use less pins.  The downside is a longer dry-time.  The last thing you want is your hard-work getting musty from being damp for too long.

• Divide ’em up!  A big patchwork project might have dozens of motifs to block.  For your sanity, block then in batches.  As a bonus, this will provide you with finished, blocked pieces you can use as a templates when blocking the rest.

Blocking Materials

Eucalan lavender smells like project success to me!
Blocking on a cork tile
A blocking board

PINS: T-pins work great as they are larger and sturdier than typical sewing pins (though these will work fine too). Whatever you use, just make sure they are rust-proof! You can never have enough pins, so buy more than you think you need! 

KNIT BLOCKERS: These are one of those things I didn’t know I needed until someone gave them to me (thanks, Cara!). Knit Blockers are like little combs with a line of pins that allow you to pin large straight edges faster and easier.  

BLOCKING WIRES: If lace is your thing, blocking wires may be worth investing in.  These thin, flexible wires can be threaded right through the edges of your knitting or crochet and pinned down to allow for maximum stretch with smooth edges. 

WOOL WASH: A no-rinse washing detergent like Eucalan or Soak can be added to your water when soaking pieces during the wet-blocking process.  This stuff is great for washing finished hand-made and delicate items and some washes have the added benefit of conditioning (ie softening) certain fibres. 

BLOCKING SURFACES: There are matts available specifically for knit and crochet blocking, but you don’t have to invest in something fancy to get good results.  Basically, you need something that is flat, non-absorbent, and won’t mind getting stuck with pins.


Carpet.  Preferably wall-to-wall type short-pile, preferably in a place your work won’t be stepped on.  Roommates will appreciate careful removable of all pins post-blocking process.

• Bulletin board. Take it off the wall and lie it flat so gravity won’t do a number on your crochet.

• Cardboard.  Cover a piece of cardboard in a plastic bag and voila!  For years I blocked things on cardboard quilting board (like this) covered in a clear bag.


• Cork tiles.  I’ve found them cheap at dollar stores and added grid lines with pen.  These are great for small pieces.

• Foam play mats.  In my experience, these seem to be the most popular blocking surface out there. They’re super-versatile as you can interlock as many pieces as you like.


• Blocking mats. These sets are the upgrade to the foam play matt option. Check out Cocoknits and Knitpicks.

• Blocking board. If patchwork projects are your jam, you may want to invest in one of these boards that is specifically designed to block multiple motifs. Squares can be pinned in stacks to ensure they all block to the same size. 

Well, that’s about all I’ve got on the blocking front.  I hope there are a few pearls of wisdom in there.  Let me know your blocking tips and tricks in the comments below!

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