If you've ever walked into The Wool Shop with a PetiteKnit pattern in your hand, there's a pretty good chance we've ended up talking about yarn substitutions.

It's one of the questions I get asked most often, and honestly, it's one of my favourite conversations to have.

There are a couple of reasons we don't stock many of the original PetiteKnit yarns. The first is that we try, wherever we can, to stock yarns that are made in New Zealand or are readily available in New Zealand and Australia. We want to support local mills where we can, make it easier to get extra yarn if you need another ball halfway through a project, and reduce some of the environmental impact that comes with importing yarn from overseas.

The second reason is that we simply live in a different climate.

One of my favourite things is when Scandinavian visitors come into the shop and are completely gobsmacked by the quality of our New Zealand yarns. We often think the grass is greener somewhere else, but the grass here grows some pretty incredible sheep, and those sheep produce some pretty incredible wool.

That doesn't mean Scandinavian yarn isn't wonderful. It absolutely is. But it does mean that we have some fantastic alternatives that are often better suited to the way we wear our knitwear here in New Zealand and Australia.

When I'm recommending a substitute, I'm not just looking at the gauge. I'm looking at how the finished garment is going to behave. Is it going to drape the same way? Will it hold its shape? Is it warm without being heavy? Will it suit our climate? Most importantly, is it going to be something you'll actually enjoy wearing?

These are the substitutions I find myself recommending most often. They're based on handling the original yarns, knitting and blocking many of the alternatives myself, and helping hundreds of customers find the right yarn for their projects.

Every pattern is a little different, so think of these as my favourite starting points rather than hard-and-fast rules.

If your pattern uses Peer Gynt

Peer Gynt appears in so many PetiteKnit patterns, and it's not hard to see why. It's a durable, non-superwash Norwegian wool that creates beautifully structured garments. It's particularly lovely for textured knitting, cables and sweaters that you want to last for years.

One thing that surprises people is that Peer Gynt isn't especially soft. It's actually a little rustic. Those slightly coarser fibres are part of what makes it such a strong, hard-wearing yarn, so when I'm choosing a substitute I'm looking for more than just the right gauge. I'm also looking for yarns that have that same durability and structure.

If you're working to a budget, I quite often recommend Red Hut Pure Wool. It's one of the best-value pure New Zealand wools we have. It creates a similar style of fabric, blocks beautifully and gives you a lovely traditional wool sweater. Because it's an affordable yarn, you may notice a little pilling initially, but that usually settles down quickly and it's fantastic value for money.

If you've got a little more room in the budget, I'll usually point you towards The Woolly Yarn Co Pure Wool, Dunes by Sun Dunes, or Yarn Flo. All of these produce beautiful, woolly garments with excellent stitch definition and the sort of structure that suits these patterns so well.

One slightly unexpected substitute I recommend quite often is Crucci Alaa. It's a blend of merino and New Zealand alpaca, so it's a different yarn altogether, but it creates a lovely full fabric that works beautifully in many of the same patterns.

If softness is your biggest priority, then I'll often move away from trying to recreate Peer Gynt exactly and recommend something like Heirloom Merino Magic 8 ply instead. It won't behave exactly the same, but if you know you'll enjoy wearing a softer sweater, that's a compromise I'd happily make.

If your pattern uses Double Sunday

Double Sunday is another yarn that comes up over and over again, and quite often you'll see it paired with Peer Gynt in different PetiteKnit designs.

The first thing I'll usually ask is whether staying with a non-machine washable yarn is important to you. If it is, I'll often recommend Dunes by Sun Dunes, The Woolly Yarn Co, Yarn Flo, or Crucci Alaa. They all create lovely fabrics with enough body to suit the kinds of garments Double Sunday was designed for.

One thing that's worth remembering is that not all double knits are created equal. Double Sunday has a little more body than many of the finer 8 ply yarns, so I'm looking for something with a bit more substance rather than simply matching the label.

If you're happy using a machine washable yarn, your options become even wider. Crucci Merino is one I recommend regularly because it's lovely to knit with and comes in a fantastic range of colours. Broadway DK is another yarn I reach for because it gives you that slightly fuller fabric that works so well in these patterns.

If budget wasn't part of the conversation and the colours lined up, I'd probably choose Dunes most of the time. It's simply a beautiful yarn to knit with.

One thing to keep an eye on is the metreage. Double Sunday gives you around 120 metres per ball, whereas many of our New Zealand and Australian yarns sit closer to 100 or 105 metres. That usually just means allowing an extra ball or two when you're planning your project.

If your pattern uses Sunday with Tynn Silk Mohair

This is probably the substitution I talk people through most often.

One little thing that's helpful to know is that tynn simply means thin in Norwegian. Sunday itself is actually finer than many of the standard 4 ply yarns we stock here. It's closer to a very fine fingering weight, so that's worth remembering when you're choosing alternatives.

One of the biggest mistakes I see is people assuming they can simply hold two standard 4 plies together. Most of the time, that creates a fabric that's heavier than the pattern was designed for.

For the base yarn, I usually look for something finer. Touch Yarns Fingering Weight is lovely, as is Broadway Supremo if you're happy with a superwash yarn. If you'd rather stay with untreated wool, Crucci Greywacke, Crucci Naturals and Crucci Pure Wool all work beautifully. Don't worry that they're pure wool. Once you add the laceweight strand, the finished fabric is still incredibly soft.

For the second strand, I normally recommend Silky Kid, Kid Cotton, or Lana Grossa Setasuri. If you don't enjoy mohair, a laceweight alpaca can also work beautifully and gives you a slightly different finish.

If someone tells me they simply don't want mohair, I don't try t

o convince them otherwise. Instead, I'd usually suggest moving to a double knit that meets the gauge rather than trying to recreate the fabric with two thicker yarns. It won't behave exactly the same, but I'd much rather help you knit something you'll genuinely enjoy wearing.

If cost is the issue, one of the easiest ways to save money is to choose a more economical base yarn while still keeping the laceweight strand. It gives you much of the softness and loft while bringing the overall project cost down.

If your pattern uses Kos

Kos is one of those yarns that people often fall in love with because of the finished garment rather than the yarn itself.

Those beautiful cloud-like sweaters look incredibly soft, warm and light, and that's because Kos is what's called a blown yarn. Instead of being spun into a traditional strand, the fibres are blown into a fine mesh tube. Much of the yarn is actually air, which is what makes it feel so light while still being wonderfully warm.

When someone asks me for a substitute, the first thing I ask is, "What is it that you loved about the original garment?"

If it's that light, airy feeling, then my first recommendation is almost always Chaska Alpaca Air. It creates a very similar style of fabric and, personally, I actually prefer it. I find it softer than Kos, and I think it suits our New Zealand and Australian climate beautifully.

Another yarn I love is Indiecita Baby Brushed Alpaca 14 ply. This would probably be my personal choice. It creates an incredibly soft garment with beautiful drape. It doesn't have quite the same structure as Alpaca Air, but it comes in a wider range of colours and is often easier for us to source.

If budget is the biggest factor, I'd often look at Crucci Alaa 12 ply instead. It's a different style of yarn, so it's important to understand that the finished garment won't have quite that same airy, cloud-like quality. Instead, it'll feel more like a traditional knitted sweater, and that's absolutely okay as long as that's the result you're expecting.

One of the biggest things I've learnt about yarn substitutions is that matching the gauge is only half the story.

You're really trying to match the finished fabric.

Need a hand working out quantities?

One of the trickiest parts of substituting yarn isn't actually choosing the yarn.

It's working out how much you'll need.

Even when two yarns knit to the same gauge, they often have different metreage per ball, so the number of balls you need can change.

If you've chosen your pattern and you've decided which yarn you'd like to use but you're not sure how much to order, just get in touch.

Send us the pattern, tell us which size you're planning to knit, and let us know which yarn you'd like to use. We'll happily help you work out the quantities before you place your order.

I'd much rather spend five minutes helping you work it out before you cast on than have you discover halfway through your project that you're one ball short.