Hibiscus cannabinus (kenaf) is an annual fiber crop grown in warm seasons and known for its remarkable productivity; it has been cultivated worldwide for thousands of years as a fiber source. While every part of the plant can be utilized for some purpose, its primary significance lies in the diverse applications of its cellulosic fiber. Kenaf features a blend of long bast and short core fibers, rendering it suitable for various industrial uses. Initially utilized for cordage and livestock feed, kenaf’s applications have expanded over the last century to encompass its utilization as paper pulp, biocomposites, textiles, biomass energy, seed oil, filtration aids, industrial absorbents, and even as a component of potting medium or as a potential source of medicine. Although traditionally a niche crop, the discovery of its diverse applications positions kenaf for rapid expansion in production in the upcoming decades. This article aims to explore the manifold applications of kenaf, highlighting those with the greatest future potential and discussing those that hold promise for commercial-level application with additional research.

Kenaf (Hibiscus cannabinus) core, an abundant renewable byproduct rich in cellulose and hemicellulose, has emerged as a candidate to replace or supplement peat and coco coir in soilless culture. This review synthesizes the physical, chemical, and biological performance of ground kenaf core and benchmarks it against conventional substrates. Kenaf core exhibits low bulk density (0.06 to 0.15 g cm⁻³), high total porosity (approximately 90%), and substantial plant available water (approximately 42%), supporting root aeration and water supply. Its pH (6.0–7.2) is near optimal for most crops, whereas electrical conductivity (EC) (3.2–4.7 dS m⁻¹) can exceed recommended ranges for salt-sensitive species, which necessitates pre-leaching or blending. Growth studies show comparable shoot and root performance in blends containing 20 to 70% kenaf, with composted kenaf often outperforming raw core. Pure kenaf generally requires more frequent irrigation and may shrink at high proportions. We outline processing variables such as core purity, particle size, composting, and leaching that govern stability and plant response, identify critical data gaps (including standardized EC and pH methods, and long-term shrinkage), and frame a sustainability agenda. Practically, studies to date indicate that pre-leached kenaf core, incorporated at up to about 70% by volume into peat or coir-based blends with structurally stable components such as perlite, can maintain growth and quality for several ornamental and bedding crops under greenhouse and nursery conditions. At the same time, reports of poor performance in some conifers and early suppression in direct-sown vegetables underscore that the suitability of kenaf-based substrates remains crop specific and dependent on material processing and management.

Kenaf (Hibiscus cannabinus) is a versatile fiber crop known for rapid growth and high biomass productivity that is often cultivated in warm-season regions where root-knot nematodes (RKNs) are prevalent. Here, we compared eight kenaf genotypes with Hibiscus acetosella and Hibiscus sabdariffa to evaluate resistance versus susceptibility to five RKN (Meloidogyne spp.) populations in two replicated greenhouse trials. The nematode panel comprised globally dominant species (M. incognita races 2 and 4, M. javanica) and emerging high-impact threats in warm-season systems (M. floridensis and M. enterolobii), which overlap geographically with current and potential kenaf production. Reproduction and galling were quantified using eggs per system, eggs per gram of root, egg masses, gall index, and reproduction factor, and genotypic differences were assessed by nonparametric rank-based tests at α = 0.05. Across nematode species, H. acetosella and H. sabdariffa showed minimal reproduction and galling, whereas most kenaf genotypes were highly susceptible. Susceptibility was most pronounced to M. enterolobii and M. floridensis, and several kenaf lines (‘Whitten’, ‘G 14’, ‘G 32’, ‘Yue 74-3’) had the highest egg counts and near-maximal egg masses and galling. M. incognita race 2 and race 4 produced strong contrasts, with H. acetosella and H. sabdariffa remaining resistant while multiple kenaf lines exhibited heavy reproduction and severe galling. M. javanica followed a similar pattern, with ‘G 32’, ‘Yue 74-3’, ‘Whitten’, ‘G 14’, and ‘74200 I4’ being highly susceptible. These results identify H. acetosella ‘PI 500707’ and H. sabdariffa ‘X17’ as robust donors of RKN resistance and highlight the susceptibility of cultivated kenaf genotypes, underscoring urgent breeding and integrated management needs for kenaf in warm-season production regions.

Hybrids between various species of Hibiscus in the Muenchhusia section are popular in commercial markets due to their colorful, floriferous blooms. However, many commercial cultivars are too vigorous for use in smaller garden spaces and often have only a few flowers in bloom. Stable, heritable mutants exhibiting dwarf stature and better branching architecture will be valuable to the commercial production of hardy Hibiscus . The goal of this project was to induce stable, heritable mutations using ethyl methanesulfonate that result in increased branching and a dwarf compact phenotype and introgress the compact phenotypes into lines of hardy Hibiscus to generate a series of diverse compact cultivars for use in commercial markets. Multiple mutations associated with dwarf, compact phenotypes were successfully induced. Hybridizations were made between M2 plants displaying a dwarf phenotype and hybrids developed through conventional breeding that do not possess the dwarf mutation in their background to develop diverse selections of dwarf plants. Inheritance patterns of the dwarf genes were determined through the segregation ratios of the dwarf phenotype in the F ₁ and F ₂ generations of these hybrids. Compared with wild-type progeny, dwarf progeny had shorter internode lengths and a greater number of primary branches.

Kenaf (Hibiscus cannabinus L.) is a warm-season fiber crop with high biomass potential, but breeding is limited by susceptibility to root-knot nematodes and ploidy barriers that hinder hybridization with resistant tetraploid relatives such as H. acetosella and H. sabdariffa. This study evaluated induced polyploid kenaf for morphological, biomass, and stomatal traits to assess its suitability as bridge germplasm. Tetraploids were generated from diploid ‘Whitten’ and ‘H.C. 584’ using colchicine, and triploids were produced in ‘H.C. 584’ by crossing diploid and tetraploid plants. Five genotypes were propagated from cuttings and evaluated under greenhouse conditions for 60 d. Tetraploid plants were shorter than their diploid counterparts in both genotypes, with ‘Whitten’ decreasing 12% and ‘H.C. 584’ 18%. Leaf width increased in tetraploids, whereas stem diameter and leaf length were unaffected by ploidy. Stalk dry weight did not differ significantly among ploidy levels within a genotype, indicating that reduced plant height did not reduce early stalk biomass accumulation. Stomatal length and width increased markedly with ploidy, with the largest stomata observed in tetraploids. These results support induced tetraploid kenaf as promising germplasm for overcoming ploidy barriers in breeding.