I started with washing and ironing it to take a "before" picture to compare with. It is a simple petticoat, gathered to a waistband, buttoned in the back, and with a single tuck at the bottom. I will make the hems deeper on any future petticoats, but all in all this one is tolerable. It's sewn with a back stitch at the seams, and the hem and tuck is sewn with a running stitch. In real life it should be worn with a number of additional petticoats for fullness, but I didn't want to wear them on this picture, since the whole point was to see what the starch could do. So it looks like a wet dishcloth on this picture.
I had read that both corn starch and potato starch were used in the period. Since corn was close to non-existing here in Sweden at the time, I used potato starch. So, from what I'd read, you should stir the starch in boiling water. What I forgot was what happens when you do that with potato starch.... it turns to jelly! Complete disaster!
I laughed about it, poured the horrid mess in cold water so as to be able to touch it and squeezed it to a jelly-mess. I then poured it through a sieve to get rid of the big lumps. I hoped that there would be enough starch left after I threw the jelly-lumps away.
I put the petticoat in the cloudy starch, soaked it and then wringed it, and hung it up to dry. It had a soapy feeling, and I did my best to hang it in such a way as to not let it stick together while drying. And then I went to my parent's for a week.
Today I came home, and ironed the petticoat. It is lightly starched, so it's not a complete disaster after all. Still I wouldn't mind to have it starched a bit harder. Anyway, it is crisp and has a sort of shiny finish to it, which I imagine will make it harder for dirt to get a good hold. It actually looks very nice.
So this is the "after" picture. Next time I'll use cold water, and see if that makes a stronger starch. At least it won't leave a sink of jelly for me to get rid of.
I'm so far managing to keep my urge to make a 14th century kirtle at bay. My corded petti is getting more and more... corded. I'm now working on the 24th row of cording. And tomorrow (hopefully) I'll be able to start on my friends wedding dress.