A provisional cast on is a cast on that is meant to be removed later. According to Merriam-Webster, the adjective provisional means: “existing or accepted for the present time but likely to be changed”. This is the perfect definition for this cast on.
This type of cast on is used if you are going to work a border after completing the knitting, or you want to graft the beginning and end of the piece together.
Picture this: You want to make a sweater from the bottom up with a fancy lace border along the hem. You can’t decide which fancy lace border among the hundreds of possibilities, but your fingers are itching to start that soft ocean- blue sweater. Use a provisional cast on and fly away knitting on the body of the sweater, knowing with joy and glee that you can very easily add a lace border at the hem later without a seam or having to pick up stitches from the cast on edge.
Another scenario: You are making a scarf that may want to become a cowl. You can ask your scarf this while you knit: “Dear scarf, would you rather be a cowl?” Instead of seaming the beginning and end of the scarf, use a provisional cast on and either graft the live stitches at the beginning and end, or do a three needle bind off with those live stitches. Grafting, (also known as Kitchener stitch) makes a virtually invisible join, and the three needle bind off makes a nice, smooth non-bulky seam. If your scarf says near the end of completion, “No, dear knitter, I don’t want to be a cowl”, then you can place the provisional cast on onto a knitting needle and bind off from there. (Isn’t it fun to converse with your knitting?)
But wait… There’s MORE!
For those of you who are extra fussy about your knitted bind off looking different than your cast on, you can use a provisional cast on at the beginning of your project as it looks almost identical to a knitted bind off! Who knew? (Of course you have enough sense to use the working yarn, not waste yarn, and if you are being particularly correct today, we wouldn’t call this a “provisional” cast on now, would we? But I digress.)
There are a few different ways to make a provisional cast on. My favorite way is to crochet a chain around the knitting needle. Use a smooth yarn in a contrasting color to produce the provisional cast on. This is known as “waste yarn”. (Is there really such a thing as waste yarn?) When you have cast on the required number of stitches, cut the waste yarn and place a couple of knots at the end of it. This will tell you at which end you will eventually remove the stitches from. “Why?” you might ask, you clever knitter! Because the crocheted chain will only release from one end and not the other. Think of an old fashioned bag of flour with a string closure across the top. It only releases from one end to get that satisfying unzipping of the bag. Otherwise, you pick and cut and waste half a day trying to get that silly bag of flour open!
When your pattern calls for any special combination of stitches, such as ribbing, increasing, decreasing, lace, etc, you will always work a plain row before you commence the pattern. (Commence. Good word.) Work one row of knit or one row of purl before beginning a pattern. If you work in ribbing, or any combination of knits and purls directly from the provisional cast on, the stitches will not unzip, and you will spend half a day undoing the provisional cast on. Ok, maybe not half a day, but it is a real drag. Working a decrease or increase is also not recommended from the waste yarn as those will also unduly involve the provisionally cast on stitches.
When removing a provisional cast on to place it back onto the knitting needle, you will have one fewer stitch than you cast on. What? Ok, ok, I will explain. If you think of your knitting when it is right side up, the stitches look like a series of: VVVVVVVVV’s. It is not a series of VVVVVVV’s with an extra slash at the end \. When you turn the work to start the additional border or bind off, you are looking at the stitches upside down.Now it is a series of /\/\/\/\’s without a complete /\ on each end, merely a half stitch \ or / and you must work one of those half stitches to equal the cast on number. Those half stitches will not drop anywhere, so if it is not important for your stitch number, you don’t need to pick up that half stitch. Ok, you had to ask didn’t you? You really didn’t want to know all that, did you?
Once you have the provisional cast on removed to a working needle, you can knit in the other direction, or graft the two live ends together. https://www.youtube.com/watch?v=wE7lPJlwlt0
You can also join the two ends with a three needle bind off.
