Hemp
A strong stem fiber, made wearable.
Reviewed 2026-09-22. Evidence level: verified. Open the interactive profile and route map.
Key figures
- US federal THC ceiling
- not more than 0.3% delta-9 THC, dry weight basis (7 U.S.C. 1639o)
- EU CAP THC ceiling
- 0.3% from 1 January 2023 (previously 0.2%)
- Cellulose in long bast fiber
- about 55 to 72%
- Lignin in long bast fiber
- about 2 to 5%
- Stalk composition
- roughly 20% bast fiber and 80% hurd by mass
Approximate values under the stated conditions.
Overview
Production: about 60,000 tonnes of hemp fiber and tow (global hemp fiber and tow, 2019). [6]
Bast fiber from hemp stems; processing can retain long fibers or create shorter cottonized fibers.
Feel and behavior
Textured and firm in some fabrics, much softer in fine yarns or blends.
Where you find it
Shirting, denim blends, canvas and home textiles.
Source and geography
Industrial hemp is Cannabis sativa L. grown for stem fiber, the woody inner core called hurd, and seed. In US federal law, the Agriculture Improvement Act of 2018 defines hemp as Cannabis sativa L. and any part of it with a delta-9 tetrahydrocannabinol (THC) concentration of not more than 0.3% on a dry weight basis (7 U.S.C. 1639o). China has long been the leading producer of hemp fiber. In Europe, France has long been among the main producers, and EU farm-support rules also use a 0.3% THC limit.
Advantages
- Hemp fiber is strong and abrasion resistant, suiting workwear, bags and canvas.
- It absorbs moisture and dries relatively fast, feeling cool like linen.
- Fabrics soften noticeably with washing while keeping their structure.
- Its fast growth and dense canopy can suppress weeds early, reducing but not eliminating herbicide needs.
Drawbacks
- Pure hemp wrinkles readily and can feel stiff or scratchy when new.
- Cottonizing and degumming for soft fabrics add chemical and energy inputs that the word hemp does not reveal.
- Supply is concentrated in a few producing countries, so traceability can be limited.
- Blends often contain only a small hemp share, which can make marketing misleading.
Worth knowing
Types, grades and fabrics
Types and grades
Hemp textiles come in two main fiber forms. Long hemp is hackled and spun on flax-type systems, often wet spun, giving strong, linen-like yarns with visible slubs. Cottonized hemp is cut and degummed to cotton-like staple so it can be blended and spun on cotton machinery; it is softer but loses some of the long fiber's strength. Fiber color and hand depend on retting and degumming: dew-retted fiber is grayer and harsher, while chemically or enzymatically degummed fiber is paler and softer. Fiber hemp varieties differ from seed and cannabinoid types in being bred for tall stems and bast yield, and in the EU only listed varieties under the THC limit qualify for farm payments.
Fabrics and products
Pure hemp is woven into canvas, heavy shirting, table linen and rustic plain weaves that resemble linen. Hemp denim, usually a hemp and cotton twill, is common, as are hemp and cotton jersey for T-shirts and hemp fleece for sweatshirts. Blends with lyocell, modal or silk add drape and softness, and blends with recycled polyester add abrasion resistance and quick drying for bags and outerwear. Blend ratios range from minority hemp in a cotton knit to majority hemp in woven cloth. Coarser hemp goes into rope, twine, webbing, mats and nonwoven insulation, and hurd is used separately in building materials.
Buying and care
How to judge quality
Check the content line first: many 'hemp' products are minority hemp blends, and the percentage by weight must appear on the label. Long-fiber hemp looks slubbier and crisper than cottonized hemp, which can feel almost like cotton. A dense, even weave with few loose fibers wears better. Harshness in new fabric is normal and eases with washing, but prickly protruding fiber ends suggest coarse, poorly degummed fiber. Claims of built-in antibacterial or UV protection need test data for the specific fabric. Organic claims should be backed by GOTS or OCS certificates that cover the product, and 'grown without pesticides' is a farming claim that the finished cloth cannot prove.
Care in detail
Machine wash hemp at 30 to 40 C with a mild detergent, washing similar colors together, since natural and dark dyed hemp can bleed in early washes. Blends follow the care needs of their most delicate fiber. Line dry where possible or tumble on low, and remove while slightly damp to reduce creasing. Pure hemp tolerates a hot iron, about 200 C, best with steam while damp, like linen; lower the setting for blends with synthetics or silk. Avoid chlorine bleach, which weakens cellulose and yellows some finishes. Store dry to prevent mildew, and do not worry about early stiffness, which usually eases after several washes.
Care at a glance
Follow the label. Wash with similar colors and avoid excessive drying heat.
Environmental and social footprint
Hemp is often promoted as a low-input crop, but evidence is uneven. Its fast canopy closure and dense planting can suppress weeds, yet a 2025 review in the Journal of Cannabis Research notes that early-season weed competition still reduces yield and that few herbicides are registered for the crop, a gap for growers rather than proof of zero chemical use. Water and energy comparisons with cotton and polyester, such as the 2005 Stockholm Environment Institute report prepared for BioRegional and WWF Cymru, depend heavily on assumed yields and processing routes. The largest variable burden is processing: water retting, alkaline degumming and cottonizing consume water, chemicals and energy.
Tradeoffs
Retting, separation and softening determine much of the processing burden. Hemp is not automatically chemical-free.
A useful question to ask: Was it mechanically processed or cottonized, and what share is actually hemp?
Science
Data sheet
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 1.40 to 1.50 g/cm3 | compiled literature range | [1] |
| Elongation at break | 1 to 4 % | compiled literature range | [1] |
| Thermal decomposition | about 220 to 350 C | thermogravimetry; onset of hemicellulose and amorphous cellulose breakdown about 220 to 250 C, main cellulose mass loss about 300 to 350 C (review value shared by cotton, flax, jute, hemp and sisal) | [1] |
| Elementary fiber length | 15 to 25 mm | single bast cells; technical fibers are much longer bundles | [2] |
| Tensile strength | 270 to 1110 MPa | compiled literature range | [1] |
Cellulose-rich plant material
Seed, stem, leaf or other plant structure. Extraction and preparation vary.
Structure and chemistry
Hemp bast fibers form bundles in the outer stem around a lignified woody core; by mass the stalk is roughly one fifth bast fiber and four fifths hurd. The long bast fibers are about 55 to 72% cellulose with about 2 to 5% lignin, together with hemicellulose, pectin and waxes. As in flax, the elementary fibers are polygonal plant cells with a lumen and show transverse dislocations (nodes), and they are cemented into technical bundles by pectin and hemicellulose. Reported fiber lengths and diameters vary widely with variety, retting and measurement method, so single values should be treated with caution.
From source to yarn
Stems are cut and usually dew retted in the field, though water, enzymatic and other degumming methods are also used. Decortication then breaks the stem and separates fiber from hurd by breaking and scutching. For long-fiber yarns, the fiber is hackled and spun on flax-type long-fiber systems, often wet spun for finer counts. Alternatively, fiber can be cut and cottonized, using mechanical opening and sometimes chemical or enzymatic degumming, to lengths suited to short-staple cotton spinning and blending. Hurd is used separately for animal bedding, building materials and composites.
Performance in use
Hemp shares many flax characteristics: high strength and stiffness, low elongation, ready moisture uptake and quick release, poor wrinkle recovery, charring rather than melting, and dyeability with cellulose dye classes such as reactive and vat dyes. Coarser, more lignified fiber gives a harsher hand and a slightly more yellowish tone, and fabrics usually soften with laundering. Cottonized hemp blended with cotton behaves much like cotton in handle and care. Claims of inherent antimicrobial, UV-blocking or thermal performance vary with fiber preparation and fabric construction and should be backed by test data for the specific product.
How it is identified
Burn tests are indicative only and need fire precautions; hemp burns like other cellulose fibers, leaving soft gray ash. Under the microscope it looks much like flax, with nodes and cross markings, so separating the two is a known analytical difficulty. Laboratories combine methods such as the direction of twisting as a wet fiber dries, staining for lignin, and spectroscopy. In cottonized blends the hemp share is difficult to confirm by eye, so percentage claims rely on supplier documentation and quantitative analysis.
History
Timeline
- Early NeolithicWhole-genome resequencing of 110 accessions indicates that Cannabis sativa was first domesticated in East Asia in early Neolithic times. [3]
- 1937The US Marihuana Tax Act of 1937 burdened cannabis cultivation, including fiber hemp. [4]
- 1942The US government released the film Hemp for Victory urging farmers to grow hemp for rope and cordage while imported fibers were scarce. [4]
- 2018The 2018 Farm Bill defined hemp as Cannabis sativa with no more than 0.3% delta-9 THC on a dry weight basis, separating it from marijuana in federal law. [5]
- 2019World production of hemp fiber and tow was about 60,000 tonnes, about 1.7% of natural fibers and about 0.05% of all textile fibers. [6]
Hemp developed a long history in rope, canvas and other strong textiles. Contemporary apparel uses both long-fiber preparation and cottonized blends. The current interest in hemp brings old processing questions into new product categories.
The deeper record
Hemp was long a cordage and heavy-cloth fiber. In the United States, the Marihuana Tax Act of 1937 burdened cannabis cultivation, including fiber hemp. During the Second World War, when imported cordage fibers were scarce, the US government produced the 1942 film Hemp for Victory to encourage farmers to grow hemp for rope and cordage, including for the Navy; after the war, cultivation declined again. Largely forgotten, the film resurfaced around 1989 in hemp advocacy. The 2018 Farm Bill separated hemp from marijuana in federal law, reopening commercial cultivation under state, tribal and USDA production plans.
Labeling and law
In the United States, hemp textiles are labeled with the fiber name and percentage by weight under the Textile Fiber Products Identification Act (15 U.S.C. 70 et seq.) and 16 CFR Part 303. THC limits govern cultivation, not garment labeling: the 2018 Farm Bill removed hemp at or below 0.3% delta-9 THC from the Controlled Substances Act definition of marijuana. In the EU, since 1 January 2023 the Common Agricultural Policy framework under Regulation (EU) 2021/2115 allows payments for approved hemp varieties with THC up to 0.3%, raised from 0.2%. EU labels follow Regulation (EU) No 1007/2011.
This describes what rules and standards cover. It is not legal advice; jurisdiction, product form and current rule text control.
Frequently asked
Is hemp fabric the same as linen?
No. Hemp comes from Cannabis sativa and linen from flax, Linum usitatissimum, although both are bast fibers and look and behave similarly. Hemp is typically slightly coarser and more yellowish, and both wrinkle, feel cool and tolerate hot ironing.
Does hemp clothing contain THC?
No meaningful amount. Fiber comes from the stem of industrial hemp varieties with very low THC, and retting, spinning, scouring and dyeing leave no psychoactive effect. THC limits govern cultivation, not garment labeling.
Does hemp fabric get softer?
Yes. Hemp's stiffness comes partly from residual gums and lignin, and washing and wear gradually loosen and flex the fibers. Cottonized hemp and blends start softer; pure long-fiber hemp takes more washes to break in.
Is hemp always more sustainable than cotton?
Not automatically. Hemp can grow with little irrigation and dense planting helps suppress weeds, but degumming and cottonizing add chemical and energy inputs, and published comparisons rely on assumptions about yield and processing. The specific supply chain matters more than the fiber name.
Sources
- Alliance for European Flax-Linen & Hemp: All about European flax
- Food and Agriculture Organization: Jute and hard fibres
- US Code (House Office of the Law Revision Counsel): 7 U.S.C. 1639o, Definitions
- Congressional Research Service: The 2018 Farm Bill's Hemp Definition and Legal Challenges to State Laws
- Materials (MDPI): Hemp Fibre Properties and Processing Target Textile, a review
- Cellulose (Springer): Extraction of cellulose fibers from flax and hemp, a review
- UNCTAD: Commodities at a Glance, special issue on industrial hemp
- Journal of Cannabis Research: Herbicide use and weed management strategies in hemp cultivation (2025)
- Stockholm Environment Institute: Ecological footprint and water analysis of cotton, hemp and polyester (2005)
- RSC Advances: Natural fibers in sustainable materials, extraction technologies, fiber modification, and performance-sustainability relationships (2026)
- ISO 3758:2023, Textiles, care labelling code using symbols (ISO Online Browsing Platform)
- Plants (2026): Improving ramie fiber, current progress and future directions in molecular breeding
- Science Advances (2021): Large-scale whole-genome resequencing unravels the domestication history of Cannabis sativa
- Wikipedia: Hemp for Victory (1942 film)
Cite this page
Chaos. (2026). Hemp. In Fibers of Earth: An independent textile atlas. https://www.hendrickresearch.com/fibers/materials/hemp/