BTS CAL Yarn Requirements

So you want to go yarn shopping or see if your stash has enough yarn for the Beneath the Surface CAL. Well, you’re in the right place!

The Beneath the Surface Crochet Blanket pattern is best made in a light weight yarn, one main colour with a contrasting colour for the surface crochet.  You can do whatever you want though!

For my blanket, I used Bendigo Woollen Mills 8 ply cotton yarn in Glacier for the base of all squares and used the same yarn in Storm Cloud for the surface crochet.

Yarn Requirements

As this is a very yarn hungry, solid blanket, I really do recommend you use a light weight yarn.  Cotton is perfect.  You see, it’s very heavy, even in cotton – almost 2 kilograms.  If you use wool or another heavier yarn, your blanket may be just too heavy and you will need a lot more yarn.  It will also be much larger.  Of course, it’s up to you what yarn you use.  I just wanted to make all that clear up front.

Ideally, your yarn should match as closely as possible the Bendigo Woollen Mills 8 ply cotton I used.  If you are outside of Australia, YarnSub is a great website that compares yarns.  If you search Bendigo Woollen Mills 8 ply cotton, it will give you some almost perfect matches that you can get pretty much anywhere in the world.  Some good websites for yarn shopping are Deramores,  Love Knitting and Wool Warehouse,

If you want to do your own research and comparison, here are the BWM 8 ply cotton properties;

Weight: DK / Light Worsted
Texture: Plied
Fibre: Cotton (100%)
Needles: 4mm (6 US) (8 UK)
Gauge: 22 sts / 10cm (4″)
Balls: 200g; 485m (529 yds)
Metres/Gram: 2.43m/g (2.65yds/g)

For other options you can check out my cotton yarn test and see if any of those take your fancy.

If you choose to use a heavier yarn, consider changing the layout so it’s smaller, not doing the centre square perhaps.


If you’re not sure what colours you want to use, try out the mini taster pattern you can find here free and try out some options before making your final decision.   Some of these I made with Cascade Ultra Pima cotton and some with Bendigo Woollen Mills 8 ply cotton.

How much yarn do I need?

To make the blanket like my sample 162 cm (64 inches) square blanket using 8 ply Bendigo Woollen Mills cotton (485 metres per 200 grams), you’ll need approximately:

Main colour:  7 or 8 200 gram balls ( I used Glacier)
Surface Crochet: 3  200 gram balls ( I used Storm Cloud)

If you use a different yarn or even just a different hook size, you may need more or less yarn and your blanket will likely be a different size too.

The difference in how much yarn you will need can be quite significant.

For example, this is the same pattern, made by me with the same hook.  The larger plain blue square is made with Bendigo Woollen Mills Classic 8 ply wool.  The other is made with Bendigo Woollen Mills 8 ply cotton.  There are 2 metres per gram in this wool and 2.43 metres per gram in the cotton.

As you can see, the wool version is quite a bit larger – half an inch bigger.  It also used a lot more yarn.

The blue wool version (using weight as the basis for the calculations) used 57 metres in total while the cotton version used 46 metres in total.  When you consider that this square is made 32 times, then the extra yarn needed just for this square is 352 metres.  That’s almost an extra 200 gram ball for just this square.  Then add the extra you’ll need for the other squares, joining and border and you can see it can really mean you need a lot more yarn than I used.

How do I work out how much of my yarn of choice I need?

So what do you do if you’re using a different yarn?

Well you’ll have to do some calculations.   First up you need something to compare to, so I have listed below how many metres I used of Bendigo Woollen Mills Cotton for each of the squares in the whole blanket.  (I have slightly overstated these figures.)

4 ply (fingering)
Plain 35 metres + 6 metres for surface crochet (38.28 yards + 6.56 yards)
Puff 42 metres + 6 metres for surface crochet (45.93 yards + 6.56 yards)
Popcorn 48 metres + 6 metres for surface crochet (52.49 yards + 6.56 yards)
Prodigious 310 metres + 40 metres for surface crochet (339 yards + 43.75 yards)

8 ply (DK/light worsted)
Plain 41 metres + 7 metres for surface crochet (44.84 yards + 7.65 yards)
Puff 48 metres + 7 metres for surface crochet (52.50 yards + 7.65 yards)
Popcorn 57 metres + 7 metres for surface crochet (62.33 yards + 7.65 yards)
Prodigious 370 metres + 46 metres for surface crochet (404.64 yards + 50.30 yards)

10 ply (aran/worsted)
Plain 50 metres + 8 metres for surface crochet (54.68 yards + 8.75 yards)
Puff 57 metres + 8 metres for surface crochet (62.33 yards + 8.75 yards)
Popcorn 66 metres + 8 metres for surface crochet (72.18 yards + 8.75 yards)
Prodigious 456 metres + 50 metres for surface crochet (498.69 yards + 54.68 yards)

Next, you need to make one of the Plain Part 1 squares in your yarn of choice.  Weigh it, then using the information on your yarn label, calculate how many metres you used.

If it’s much the same or less than above, all is well.  Use my yardage calculations for the whole blanket above.

If it’s more, then you’ll need to figure out how much extra yarn you’ll need by testing the other squares as well.  For the big one, as there’s only one to be made, compare the differences between my figures and yours for the other squares and see what approximate percentage more is used.  Apply that to my Prodigious yardage to work out roughly how much extra you’ll need.

You will need to make 32 Plain Old Squares, 24 Puff Squares and 16 Popcorn Squares, as well as the one large centre square.  Plus you’ll need extra for joining and the border.


I think that covers all the yarn questions you may have.  If not, please email me and I will get back to you as soon as I can.

Happy stash diving or yarn shopping!

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