Sunflower is grown for its seed, from which high-quality oil and protein are extracted. The seeds, however only account for a small part of the plant, leaving a substantial amount of sunflower biomass unexploited. The current harvesting practice cuts the sunflower heads from which seeds are isolated. The remaining parts of the cut heads are dumped via the back of the harvester and left in the fields, together with the stems. As a result, sunflower growers would greatly benefit from new applications that create value from the unused sunflower biomass. So far, most studies have focussed on the possibility to use sunflower biomass to produce fibre. The pith of sunflower stems contains good quality fibres that can be used in various new bio-based materials, for instance as insulation or as construction material. Our previous studies have shown that the bark of sunflower stems also contains fibres that may lead to new bio-based products. In addition to fibre, we found that a side stream that is generated during bark fibre extraction is highly bioactive when applied to plants. Even more recently, we found that the side stream derived from the combined collection of cut heads and stems, from a different sunflower variety, is also highly bioactive. This intriguing property prompted further investigation and preliminary analysis showed that unused combined sunflower biomass can potentially be developed into new agricultural products and bio-based building materials. Indeed, these findings entail new opportunities for transforming sunflower biomass into renewable products that match with the forecasted sustainable bio-economy.