Today, I thought I would talk about dye lots and their importance. Dyeing is the application of colour to textiles. Yarn is dyed in batches or lots. Dye lots are numbers stamped onto the ball band, and it’s not uncommon for the same colour to vary from one dye lot to another.
Solid colors are most problematic; a definite line most likely will be obvious when you start knitting a skein in the new dye lot. I have had this happen to me and it doesn’t look very good. When I needed extra yarn, and I had no choice but to buy a new dye lot, I somewhat resolved the problem, by knitting a few rows with the old dye lot, followed by a few with the new one, a few rows in the old dye lot, and continue with the new dye lot. You could also work a different dye lot in by using it only for a sleeve or edges, such as buttonhole borders.
With multi-coloured yarns, using different dye lots may not pose a problem. Kettle dyeing yarns is an advanced technique for coloring yarn that involves manipulating the dye in the pot to produce different “looks”. A common “look” is a subtle gradation of light and dark areas of one colour. Kettle dyed yarns may not be problematic when changing dye lots, but is a personal choice as to how you want the variation of colour to look. Kettle dyed yarns and hand painted yarns naturally look different from skein to skein.
To alleviate any dye lot issues, it is recommended to buy all the yarn you need for your project at the same time, and buy an extra ball or two than what the pattern instructions call for. I hope this information is helpful, and may change your mind when you want to buy just one ball in the hopes there will be more yarn when you return to the store.