Low Humidity is Good for Dressing Flax

We are being visited by some gloriously cool, dry weather here in Amherst. The humidity has been relatively low for the past several days, so I’ve taken the opportunity to chip away at processing (otherwise known as “dressing”) my enormous back-log of flax.

I’ve been growing flax since 2004, and I’ve grown some every summer since then (except for one year). I have yet to spin any of my own fiber, mind you, let alone weave it. Very slow cloth. After all this time, the part of the process I still find the most difficult is retting.

Retting is the controlled rotting process that separates the useful bast fibers from the other layers of the flax stalk. The bast fibers run the length of the stalk. Retting separates these from the tough, waxy skin on the outside and from the woody core of the stalk at the center. Traditionally, the two ways to ret flax are water retting and dew retting. I water ret in stock watering tanks. It is a stinky process. Bacteria grow in the tank over the course of several days, and these bacteria basically eat up the pectins that hold together the layers of the stalk. The trick is to let the bacteria work just long enough but not too long. When the pectins are sufficiently broken down, the layers should separate fairly easily. If you let it go for too long, the long bast fibers themselves will break apart. If you don’t let it go long enough, the waxy skin or cuticle is really hard to remove.

Despite my efforts of the years to improve my skills at judging when retting is complete, have repeatedly under-retted my flax. I didn’t realize my first several batches were under-retted until I went to brake/break them. “Braking” or “breaking” is what it’s called when you smash up the woody pieces of the dried, retted flax, or flax “straw.” The stalks just bent but nothing shattered, and the fibers stuck together in ribbons. Too late, I’d already broken several bundles. You have to ret flax straw while it’s still intact.

Even in recent years, I have still managed to under-ret most batches, so I’ve now had the same experience quite a few times…. I think a batch is well-retted, but when I go to break it, it isn’t. I’m still trying to figure out the best way to tell when the flax is truly well-retted.

Meanwhile I have a lot of bundles of broken flax that are under-retted. What I’ve read states that under-retting makes it harder to separate the layers. So, I figured maybe it would be hard, but not impossible. I didn’t want to waste all that under-retted flax, and I was willing to work harder to get to the next step. Having spent about six days now dressing under-retted (and some nicely-retted) flax, I can now report the following:

1. It is true that you should break and scutch flax (scutching is scraping off the woody pieces or shives that remain after breaking) when the weather is dry. I can attest to this from personal experience. On a humid day in July, I broke several bundles from different retting tanks, but the shives and skin stuck on like glue. I despaired that my *whole* crop from 2012 was under-retted.

I was struck with a terrible sense of futility and doom, which remained with me for weeks. It was a bad feeling to realize that despite all my efforts all these years, I am perhaps no better at this whole flax thing than I was when I started. It was also a bad feeling to face the prospect of re-retting all that flax. Retting is a lot of work, and I wasn’t confident that I’d judge when the flax was properly retted any better this time around. Meanwhile, I had already broken those bundles. But then…

Last Thursday afternoon the relative humidity was about 40%. I decided to face my dread, and I tackled some of these broken bundles. To my surprise and delight, the shives which had clung so tightly to the fibers in July were popping off in my hands on Thursday, “Snap, crackle, pop!” So, I cleaned off a few bundles with my “hardware store tools” method, learned from Chris Hammel. Lesson learned: Don’t bother breaking or scutching when it’s humid.

2. Even though it is possible to clean up under-retted bundles, it is very hard to get the skin or cuticle off. Very, very hard. Ouch, say my hands. It takes a lot of scraping and manipulation, and a lot of what appears to be good, long fiber gets broken in the process. Then, even when the fiber looks fairly clean, the strands are stuck together with some remaining pectins and they don’t entirely separate. Consequently, they feel coarse and stiff, not silky and luscious. It’s possible that the fibers themselves are coarse. I may have let them grow too long, or there could have been too much nitrogen, or I could have planted too sparsely. A number of other factors could contribute to coarse fiber. In the stalk, the fibers are clustered together, and these clusters are also held together by pectins. I strongly suspect that, in most of my flax, the fibers are still attached to their neighbors.

These things are very useful to know. I had already read these facts. I had even been told these facts in person by knowledgable people. But I can now definitively say, from personal experience, that under-retting will reduce the quality of your fiber!