I’m working on a leafy lace (stockinette knit) scarf. This will be the first time I actually soak, stretch and block a piece and I am not sure how much I can stretch it. I don’t want to end up with a piece that is too long or too short. I read that garter can stretch up to 30% but this is stockinette.
You can block what you’ve got done now to see how much it changes. Put the sts on some other yarn and block it with the skein attached, stretching it into a size you like for the pattern to look nice. Measure before and after.