Final report for FNE24-073
Project Information
We set out to identify and increase production of open source fiber flax seed varieties available through the USDA and to evaluate them for growth, fiber quality and productivity. Our goal is to produce enough of the best open source fiber flax seed varieties to both grow at scale and use in seed breeding trials.
In 2023 we grew 68 varieties of fiber flax seed from the USDA to evaluate them for potential growth and fiber quality in our region. We then selected 13 of the most promising varieties and in 2024 we began work with Truelove seeds to grow these varieties for seed production and for fiber and to observe their performance. Our primary methods include: planting and monitoring the crop, harvesting, measuring and storing the seed and testing fiber quality both organoleptically and, eventually, microscopically and mechanically in a lab.
The growth rate of different fiber flax varieties is not significantly variable with a few exceptions. From this data we can make a very preliminary conclusion that day length seems to be more important than temperature. The differences between varieties shows up in the fiber testing done at the lab. This is a crucial step in choosing the best varieties. This season we will harvest nearly 50 Lbs of seed from 12 open source fiber flax seed varieties and ~5 acres of commercially available seed at our partner farms.
Over the life of this grant we hosted 2 winter growers meetings, 2 flax flower picnics, a webinar in collaboration with the Rodale Institute and 3 on-farm hand fiber processing events. We reached farmers, community members and others working to reestablish the flax industry in their regions. We remain optimistic about the future of fiber flax in the Northeast.
- Grow plots of increasing size to increase production of 3 -5 open source varieties of fiber flax seed we chose from our 2023 seed trials in isolation at Truelove seeds farm over 2 growing seasons
- Work with Vic Spindler-fox and Christina Nowak to create data sheets and protocols for use. Support farmers in collecting and entering data
- Record field observations and make them available to other farmers. (See attachments to this report)
- Plant educational plots of fiber flax seed at Kneehigh farm and host educational events
- Establish relationships with regional seed breeders and provide seed to them for formal fiber flax seed breeding programs
Kneehigh farm, as a founding member of PA Flax Project, is working to advance fiber flax production in Pennsylvania. Fiber flax first came to this continent with settlers arriving in Germantown Philadelphia in the 17c.. With the advent of cheap cotton and synthetic textiles after WW II, the flax industry faltered in North America and the agronomy and infrastructure has been lost in the intervening decades. Today, fiber flax is in demand globally and this is a reemerging high-value market for Pennsylvania farmers. Fiber flax is a high value, low input, 100 day early spring crop that fits well into existing rotations in our region. It has the potential to become an important revenue stream for our farmers in the Northeast.
We have identified a significant barrier to scaling fiber flax agriculture in Pennsylvania - the cost and availability of high quality seed. Currently, commercial production of fiber flax seed varieties in the U.S. is extremely limited, leaving US farmers dependent on importing seed from Europe. Importing European seed has become increasingly difficult due to both weather related seed shortages, the ever increasing cost and unreliability of international shipping.
Kneehigh Farm has been growing diverse vegetables since 2013. We cultivate 4 acres each season,with another 1.5 in annual cover crop. We have expanded into growing fiber and dye
crops for educational purposes. In 2020, Emma de Long, owner of Kneehigh farm, founded the PA Flax Project with textile artist Heidi Barr with a mission to grow textiles that are good for people and the planet and to develop a deeper relationship with everything that we are capable of producing. The expansion into fiber and dye crops has been an important community element to our farm. Growing flax for fiber has created opportunities for on-farm workshops, as well as discussions into the importance of regenerative and organic farming practices around fiber.Over the last decade, we have cultivated a rich diversity of farm partners and allies. We currently lease from Lundale Farm, a non-profit organization whose vision is to serve as a model for local food (and fiber) production on preserved land. We are happy to have the equipment, knowledge base, and connections necessary for facilitating this project.
Kneehigh Farm has been growing diverse vegetables since 2013. We produce regeneratively grown vegetables on 5 acres, and sell retail to a number of outlets, such as our CSA, our brick & mortar farm store and one farmers' market. We also sell wholesale to chefs locally as well as in & around Philadelphia. I farm part-time, and hire a part time farm manager in addition to two full-time employees. This year we are expected to gross $138,000. Farm resources that are dedicated to this project, include space for growing demonstration plots in 2024, field equipment for bed preparation and planting and Emma de Long's time and expertise with fiber flax.
Cooperators
- - Technical Advisor
- - Producer
- - Producer (Researcher)
- - Technical Advisor
- (Educator)
- - Producer
- (Researcher)
Research
We began by reviewing the plant properties and organoleptic fiber quality testing of the USDA fiber flax varieties we grew in 2023. Based on this information, we chose which seed varieties to continue working with.
Our primary methods include: planting and monitoring the crop, harvesting, measuring and storing the seed and test fiber quality both organoleptically and, eventually, microscopically and mechanically in a lab.
We are focusing on the growth, fiber quality and productivity of USDA Fiber Flax varieties at Truelove Seeds, and commercial varieties at two larger farms with a goal of producing enough of some open source fiber flax seed varieties to both grow at scale and to share for use in seed breeding trials.
Observations in season ( March - July each year) include:
•PAFP Data - Seed Stock
•Weekly Observations of crop development and weather - see attached data sheets
•Seasonal Observations, Cumulative
•Retting, how long it takes and the weather conditions
In season observations are done weekly by farmers in the field through observation, referencing weather stations, physical measurements and organoleptic fiber quality assessment. The results are then entered into data sheets in a shared google drive document.
Observations post season (August - October) include:
•Hand processing and organoleptic fiber quality observations
•Microscopic and mechanical testing in a lab
The hand processing is done using reproductions of colonial era wooden fiber flax processing tools. The organoleptic fiber testing employs a combination of human hand and eye to evaluate color, luster, strength, and length of fiber.
Flax Fiber laboratory quality analysis including microscopy, linear density, and tensile properties of a single fiber, were supported with funding outside of this grant. Flax fibers were first characterized for fineness using a Keyence digital microscope. Individual fibers were imaged at high magnification, and fiber diameter measurements were collected from multiple locations along each specimen to determine the average fiber size. Following microscopy, the mechanical properties of the fibers were evaluated using an Instron Universal Testing System. Single fiber tensile testing was conducted in accordance with ASTM D3822 to determine fiber tenacity and elongation at break
Next steps will include:
•Biomass per unit area, long fiber, short fiber and shive.Biomass per unit area information will be done after we have measurable samples to send to a mechanical processor in Canada or Europe. The result will be accomplished by weighing retted straw, sending it for processing, then weighing the resulting products.
In 2025, we integrated our learnings from the 2024 growing season and adjusted the scope of our work to maximize useful results. By paring down our in-season data points for ease of timely collection of more critical measurements.
Our data from the 2025 & 2026 growing seasons is focused on the growth and productivity of USDA Flax varieties at Truelove Seeds. We are also making observations of two commercially available varieties at our larger farm locations.
In season, we Measured
- Weather averages high & low temperatures and rainfall
- Plant height/growth rate
- Plant bloom date
- Plant harvest date
We had theorized that a late March planting date would greatly improve outcomes by encouraging plant maturity before the summer heat. Upon observation, we discovered that we did not gain much by planting early. We compared the 2025 crop planted 4/17 to the 2026 crop planted 3/19. By mid-May the plantings year over year reached approximately the same height and by mid-June approximately the same % flowering despite planting nearly a month earlier in 2026. The growth rate of different fiber flax varieties is not significantly variable with a few exceptions. From this data we can make a very preliminary conclusion that day length seems to be more important than temperature.
In 2025 we decided to eliminate data from our Square Yard participants. This reduced the burden of data collection and eliminated all the variability that comes with un-trained individuals from our final results. While we still believe there is value in a citizen scientist project like this, we recognize that it will require a different project design and the data collected will be best used to determine a different type of result, focused less on commercial scale fiber flax agriculture.
We also shifted our focus for a formal seed breeding program from an internal goal to seeking partners at area universities and with extension agents. This change means we can contribute in a meaningful way to well resourced institutions working on fiber flax seed breeding while focusing our efforts on developing the industry.
Conditions change year to year and place to place. Real world conditions give us a better understanding of best and worst case scenarios. We have had significant learnings about what is feasible as far as record keeping during the season.
We are having a 700% yearly increase in seed quantity at Truelove Seeds and now have 2,865 grams we expect to have 22,900 grams in 2026. While the progress is slower than we had initially predicted, our SARE Figures January 2026 show the exponential growth of increases for the USDA seed and indicate that we are well on our way to having enough open source seed to get more serious production going. A lack of fiber specific open source seed in bulk is the reason we can't reach 3 - 5 farms for growing seed at scale within our anticipated timeline. We continue engaging with seed breeders and commercial seed companies with the goal of working together to develop regional flax seed varieties and scale production. The fiber testing that will determine which varieties perform best in our region is well underway with year over year analysis of ~12 varieties expected to be complete by year's end.
Ideally, collecting data over 10 years would give higher likelihood of getting data that gives a holistic picture of different conditions. It is good to track quality and production in unstable weather conditions the world is now seeing. The varieties we have started with, were selected and bred over time for a more stable conditions. These last two points make a compelling case for deeper study.
Education & outreach activities and participation summary
Participation summary:
Over the course of this grant funded period we hosted two successful winter growers meetings where we engaged with research partners, industry partners and Farmers. Resulting in 3 farmers growing 45 acres of fiber flax in 2026, including 4 different commercially available seed varieties. These farms are growing primarily for fiber but will be saving seed from portions of their fields where open source varieties are planted.
We hosted 2 flax flower picnics and several informal farmer field days at three farm locations. The total attendance was 55 with 6 of them being farmers.
For our seed trial partners, we created 5 data sheets. We're collecting data in these sheets and using them as a guide to develop the database for our seed trials and seed production. These assets are stored in a google drive for ease of use and sharing and are linked in this report.
We presented a webinar called “Pennsylvania’s Re-emerging Flax to Linen Industry” with our technical advisors at Rodale Institute on November 6th 2024. We had 68 registered, 23 live attendees for a 35% attendance rate which is above Rodale’s historical average of 25%. The video has 176 views on Youtube to date. The audience was very engaged during the Q&A and the webinar is linked on Rodale’s website.
We hosted 3 on-farm hand processing events with a total of 84 attendees, 5 of them are farmers.
In addition to the 23 farmers attending the webinar with Rodale, and the 5 farmers attending processing workshops, We had conversations with 45 additional farmers interested in our work. 15 of those remain engaged, the remaining 25 have either not engaged further or are waiting to participate at a later date.
Learning Outcomes
The 83 farmers who gained knowledge includes the 23 who attended the webinar presented with The Rodale Institute and the additional 60 contacted by us through our outreach efforts.
They gained knowledge in
- Land preparation, seeding, and harvest equipment knowledge gained
- economies of scale and the flax industry at large
- Flax fitting into rotation and farm economics
- History of flax, uses of, and processing
- What qualities make flax fiber more or less valuable in the market and how to assess them in the field post harvest
- Challenges associated with sourcing seed in North America
- Seed varieties currently being trialed
Project Outcomes
While an at-scale, open source, regionally specific fiber flax seed source is still some years in the future, we have made measurable progress towards identifying both existing varieties to grow for use and to potentially work with in future seed trials. We have expanded from 4 acres of fiber flax to 45 acres of fiber flax. With a portion of this year's crop being harvested for seed, this will be the first year of a measurable fiber flax seed harvest in Pennsylvania. Even though it is not the specifically bred, regional variety we dreamed of; it nonetheless represents a new market.
We began this project with a broad multi-pronged approach which included, identifying open source seed varieties suited to our region, a citizen science community data collection component, scaling production, fiber analysis and seed breeding. In hindsight, this broad approach diluted our ability to achieve any single objective well. The areas of study that succeeded most were those where we had a strong relationship with our collaborators and our decision to focus on these ultimately provided meaningful results.
We focused our resources on identifying open source seed varieties suited to our region with our partners at Truelove seeds and then fiber testing at Jefferson University. This line of inquiry has resulted in promising data and foundation for further study as well as an increase in seed available for production.
Additionally, we focused our scaling efforts on 3 experienced farmers contracted to grow for fiber and able to save a portion of their crop for seed. This will allow a measurable fiber flax seed crop this season.
We will continue both the previously mentioned lines of research and development. We are not continuing with the citizen science collection of data through square yard project participants (community grow project). It would require more management than we have the capacity for to net meaningful results. We will also not pursue our open seed breeding program. We have learned that the results will be far more legitimate and meaningful if we partner with well resourced Universities with existing seed breeding programs.
Our trial of open source flax fiber seed varieties started small, and is growing at a good pace. As we increase our trial plot sizes, variability will be spread over a larger area which can lead to a more accurate picture of variability within each varietal. As sample size gets bigger and the number of growing seasons increase, the data that is collected goes up, certainty of results gets higher (i.e. more accurate picture of which flax varieties perform best in real-world conditions over time).
Ideally, collecting data over 10 years would give higher likelihood of getting data that gives a holistic picture of different conditions. It is good to track quality and production in unstable weather conditions the world is now seeing. The varieties we have started with, were selected and bred over time for a more stable conditions. These last two points make a compelling case for deeper study.
By looking at the data sheets linked below in this report, other fiber flax growers in the Northeast can identify promising open source varieties available from the USDA which will accelerate their process of producing seed. We hope that our methods also serve as a guide to others working towards available, reliable fiber flax seeds in our region.
3. Truelove Weekly Observations 2026 2. Truelove USDA Seed Stock 2026 1. Cover Sheet - Truelove USDA 2026 Grow Out
1. Cover Sheet - Truelove USDA Grow Out 3. Truelove Weekly Observations - 2025 4. Truelove Seasonal Observations, Cumulative