After a false start where germination was not happening and re-seeding 3 weeks after the original seeding, I have a bumper crop! Last year I harvested approximately 12 lbs of green flax straw (weighed immediately after pulling). This year my first harvest was about 29 lbs. Instead of growing all approximately the same height, it was of very varying heights, anywhere from about 12" to 36".
Since it should be collected and processed in bundles of similar height for processing, I first pulled the tallest plants 30-36", then the medium height - 22-28" (above).
I left the short stuff which was mostly 15" or less and had not flowered. I thought I would pull it in the fall or till it into the soil. The picture to the left shows what was left after the main harvest.
A couple of weeks ago I went to my allotment to check it and it had grown and flowered and was from 22" to 33" in height. So I pulled it again in two different heights and yielded a further 18 lbs for a second harvest - for the first time in 10 years of growing it. With shorter and cooler days now, I am having some difficulty drying the 'green' out of it.
I did bundle it at first, then spread it out on the deck or the lawn so that it would have a better chance to dry out, then had to keep collecting it up on rainy days.